Ryūko Matoi

"This is a keepsake from my father. And this Scissor Blade was left behind by the person who murdered him! Now, you're going to tell me who this Scissor Blade belongs to... Satsuki Kiryūin!"

- Ryūko in Episode 1.

Ryūko Matoi is the main protagonist of Kill la Kill. She transferred to Honnōji Academy searching for the twin of her red Scissor Blade and the person who used the weapon to murder her father, Isshin Matoi.

It is later revealed that Ryūko is the daughter of Sōichirō and Ragyō Kiryūin and the younger sister of Satsuki. It was also revealed that Ryūko had supposedly died after she was born after Ragyō had attempted to fuse her body with Life Fibers, which was declared a failed experiment by Ragyō herself; however, Ragyō's experiment would later be revealed to be a success. Ryūko was later saved by her father, with her father faking her death and raising her under the alias of Isshin Matoi until his death at the hands of Nui Harime. Six months after Isshin's death, Ryūko transferred to Honnōji Academy.

Appearance
Ryūko is a 17 year old girl of medium height and has blue-black hair of medium length with a single left-swept red highlight on her bangs as well as blue eyes, which have peculiar gear-like pupils with eight grooves around the edges. Her outfit at the start of the series is a white collared shirt with a red bow tie which is worn under a black & white varsity jacket with rolled-up sleeves, as well as a black skirt and white sneakers. During her childhood, she wore a red collared shirt with a white skirt and white shoes.

Baring her shoes, her clothing is later replaced by Senketsu, a living navy blue sailor uniform. Her shirt (Senketsu's upper jaw) is a dark navy sailor uniform with mid-length sleeves that bares her midriff with the collar having red stripes and is tied by a multicolored scarf that also serves as Senketsu's left "eye while his "right" eye is covered by a black "eyepatch" with an X-shaped scratch over it (perhaps emulating her father's right eyepatch). Her skirt (Senketsu's lower jaw) is held up by suspenders attached to a belt. Aikurō Mikisugi later provides her with a Seki Tekkō (赤手甲), a red, finger-less, left-handed glove with a built-in syringe designed for Ryūko to conveniently draw blood and feed it to Senketsu.

Ryūko's appearance changes further when using Life Fiber Synchronize with Senketsu. Her hair becomes even more feathery and is accented with vibrant red undertones and horn-like clips. Senketsu himself also undergoes a significant change in appearance after Synchronization; his "eyes" extend into wing-shaped crests jutting out from Ryūko's shoulders and his upper and lower parts transform into a black, skimpy suit of armor with red stripes. The top section of the armor covers Ryūko's neck, lower-jaw, arms, and upper breasts, and possesses a red, triangular ventilation grill centered on Ryūko's upper back. The top armor piece is connected to her skirt by three red garter belt/suspenders (two in front, one in back), leaving everything between the underside of her breasts and her waist exposed. Her legs are also covered with thigh-high boots with heels.

When Ryūko wears Senketsu Kisaragi, Senketsu's eyepatch is broken, revealing his hidden eye, his color scheme changes to reddish-orange and yellow, the headpiece becomes more elaborate like a rabbit's ears, yellow energy bands form a skirt that looks like jaws around Ryūko's waist and her hair becomes blonde.

Personality
Ryūko has a relatively simple personality: fierce and stubborn. She fears little, which is demonstrated when she directly and disrespectfully addresses Satsuki Kiryūin, demanding that her questions be answered, and when she fights Takaharu Fukuroda even though she is clearly overpowered. Later on, she is shown to be quite embarrassed when she is forced to fight in Senketsu's very revealing alternate form, though she overcomes her embarrassment in Episode 3 showing that while she is not afraid of fighting to her death, she is somewhat self-conscious.

Even though most of the time she is seen stubborn and fierce, sometimes she can be shown calm, polite, content and warmly flattered. This is mostly seen when eating with the Mankanshoku family and Episode 7. She admires the way Mako's mother makes food and has kind manners. She later is seen telling Senketsu how fun dinner was with them because of how her mother died when she was young and her dad sent her to a boarding school, never knowing how a family dinner was like. Her flattery is highlighted in Episode 1 when Mataro tried to steal Ryuko's wallet and mug her. She was cool with the intention of fighting, criticizing how street punking doesn't work for him and how goofy his gang was. After defeating them, she lets it slide by not fighting people who can't fight back. This is also seen with most opponents she faces when she often states the obvious.

She shows fierce determination in finding her father's killer. Her stubbornness was taken up to ridiculous levels when she managed to free herself from Ragyō's mind control by merely punching herself. This same episode, however, has one of few demonstrations of shock on her part, when Ragyō defeats Satsuki, rips out Ryūko's heart and reveals to be her mother.

When Ryūko is brainwashed after being forced to put on Junketsu by Ragyō, her personality changes to be wild and sadistic, destroying everything around her without reason. After she is freed she goes back to her usual personality but is somewhat calmer and more mature. She also makes peace with Satsuki and is able to fight with her as a comrade, but is still having trouble recognizing her as her sister. Although, after Satsuki catches her when she is falling back to earth and welcomes her home warmly, Ryūko replies by calling her "sis."

History
Ryūko's mother is initially presumed to have died after she was born and her relationship with her father, Isshin Matoi, was strained and distant. Ryūko spent her early childhood living in the dorms of Ox Elementary School as her father focused solely on his studies. A lack of guidance and being bullied by others, Ryūko became a juvenile delinquent, constantly getting into fights and even going so far as to join a gang. Six months before enrolling at Honnōji Academy she received a message from her father and returned to her home only to find him bleeding to death with a red Scissor Blade plunged into his chest. Isshin told her upfront that if she wanted to live a peaceful life, that she should get up and walk away, but if she wanted to 'fight' in his place she should take the blade, for as long as she had it she would surely be able to find his killer. Before Isshin could provide Ryūko with further information she caught sight of a shadowy female figure out of the corner of her eye wielding the other half of the Scissor Blade. Ryūko dashed outside the house but was unable to apprehend the fleeing woman. Before she could get back in an explosive device of some kind detonated and lit the house ablaze. Ryuko watched in horror, screaming for her father, but to no avail. Vowing revenge Ryūko became a wandering vagrant looking for clues behind the killer's identity and whereabouts.

Episode 1
Ryūko's search for her father's killer brings her to Honnō City, where she enrolls in its academy as a transfer student. On her way to the school she encounters Mako Mankanshoku, who she ends up sitting next to in class. Mako informs Ryūko of the Student Council that rules the academy under its president, Satsuki Kiryūin. She immediately confronts Satsuki, showing her the red Scissor Blade used to kill her father and is convinced by Satsuki's surprised reaction that she knows something about it. Ryūko is intercepted by council member Takaharu Fukuroda, who overwhelms her with the power of his Two-Star Goku Uniform.

Beaten and faced with the confiscation of her Scissor Blade, Ryūko flees to her old home near the city. As she laments her weakness, Ryūko is dropped down a trapdoor by her homeroom teacher Aikurō Mikisugi, who had followed her against her knowledge. She lands in a large basement atop a massive pile of clothes, the blood from her reopened wound seeping into it and awakening a Kamui—a living sailor uniform—created by her father. The Kamui springs to life and forcefully puts itself on her, craving more of her blood. Ryūko discovers that the uniform possesses immense power, and names it Senketsu.

Imbued with Senketsu's power, Ryūko returns to Honnōji Academy and battles Takaharu again in a boxing match, this time overcoming his Goku Uniform powers with Senketsu's indestructible armored form, and destroying his uniform with her Scissor Blade. She reveals to Satsuki that both her outfit and weapon are keepsakes from her father, and once more demands Satsuki to reveal what she knows. However, she is fatigued from her battle and retreats.

Episode 2
Ryūko retreated and collapsed when she stepped off the tram heading down the tall mountain. When she awoke, she found herself in the house of the Mankanshoku family and reluctantly had dinner with them that consisted of questionable food. Ryūko reminisced how she first met the talking Kamui uniform and partnered with it after naming it Senketsu as in “Fresh Blood”.

Ryūko came to school along with Mako and is invited to stay with the Mankanshoku family. They both found themselves under fire by the tennis club and its newly two-star Goku Uniformed captain, Omiko. Ryūko tried to fight back but found herself in trouble when she failed to awaken Senketsu. She escapes by falling into the sewers and by clinging onto her guitar case as she drifted along with the current.

Ryūko awoke to find herself in the presence of her homeroom teacher, who does not seem to be what he appeared. He extracted some of her blood with a needle, despite her excessive refusal, and showed her that Senketsu needed to be in contact with her blood to be fully utilized. Ryūko wanted answers from him but she first had to fight Omiko in a rematch and again rescue Mako.

After Ryūko saved Mako, who was being barraged by countless tennis balls, Ryūko somehow found herself fighting against Omiko in a tennis match, all due to some twisted logic of Satsuki’s minions, Uzu Sanageyama. She was able to win by using her scissor blade as a tennis racket, and with a sheer force, she blasted Omiko away, along with stripping Omiko of her Goku Uniform in the process. Afterward, Ryūko was forced to fight Satsuki and was nearly dominated by her skill with the blade. Ryūko was alerted by Senketsu that she was about to pass out due to blood loss, so she escapes along with Mako in an improvised cover of steam.

Episode 3
While meeting with Mako, she discovered a note that was pinned to Mako’s back, it was from Aikurō and it stated where they can meet. Aikurō told her about a term called Life Fibers, and how Isshin Matoi and the Kiryūin clan were the only two that knew of its full capability. She learned that Aikurō used to work as an assistant for Isshin and had infiltrated Honnōji Academy to learn more. She also learned that the Kamui’s awakened form was apparently the idea of Isshin, her father.

After spending another night at the Mankanshoku’s house, Ryūko went to school with Mako and found Satsuki waiting for her. Ryūko asked Mako to step aside for safety and readied herself to fight Satsuki, who revealed that she had her own Kamui, Junketsu, and had already mastered it. Ryūko fights Satsuki, but she is overwhelmed by her. To keep Ryūko from nearly losing consciousness, Senketsu reverted back to his dormant state to stop feasting on her blood. Before the victor was decided, Mako intervened and her speech made Ryūko finally understand the true meaning of wearing Senketsu. She finally accepted the revealing form, and now had better synchronization with Senketsu. With strength anew, Ryūko was able to fight Satsuki on the near-equal ground.

When the fight came to an end, Ryūko declared to Satsuki that she will tear down her ambitions, utterly destroy them, and then will have Satsuki tell her about her involvement with her father's murder. Satsuki accepted her claim and announced that from then on, Ryūko will be made the target of every club. Only when she defeats every opposing student in the school, will they once again fight one another, and if Ryūko wins that fight, only then will Satsuki reveal her involvement in the death of Isshin Matoi.

Episode 4
Ryūko has to participate in an annual school event called “No-Late Day”; where the students of Honnōji Academy have to go through 999 obstacles and get to class in time or risk getting expelled. During the event, she and Mako encounter a girl name Maiko Ogure, who supposedly was injured during one of the obstacle courses. They decide to take her along out of kindness; however, the girl betrays them near the end and steals Senketsu. Maiko reveals herself to be the Head of the Trap Department of the Disciplinary Committee, and she wanted Ryūko’s Kamui so she could usurp the control of the school from Satsuki. Maiko tries to attack them but her mobility is restricted by Senketsu and this allows Ryūko to beat her up and reclaim Senketsu. Afterward, Ryūko and Mako learn that they were tricked once again by Maiko’s “fake school” trap; they are able to make it to school on time by crashing into the classroom after commandeering a cable cart.

Episode 5
The episode starts with the arrival of a mysterious man with a red mohawk, who makes his way to the terrace of one of the school blocks, and positions himself with what appears to be a rifle, aiming through the window of the adjacent block. He targets Ryūko Matoi but is interrupted by the members of the gardening club who start a fight with him for trampling on their flowers. The scene then shifts, where it's shown that Ryūko faces the biology club's members who have taken Mako as a guinea pig for an unknown experiment. After defeating the members of the biology club, Ryūko scolds Mako for being careless, but suddenly Mako is shot with numerous needles, sending Ryūko in a panic. The attacker is Tsumugu Kinagase, who tells Ryūko that Mako is only unconscious and that she will feel energetic when she wakes up. He then proceeds to attack Ryūko and tells her to strip. Ryūko asks him if he belongs to a "Pervert club", but he tells her that he does not belong to any club and he stops Ryūko from transforming. Before he can finish Ryūko off, he is shot with a pin that pierces his hand, forcing him to retreat but not without warning Ryūko that he will fight her once again. The next day Ryūko and Tsumugu fight each other, but he overpowers Ryūko, even when she transforms. After a fierce battle Ryūko reverts to normal form due to exhaustion. Tsumugu then tells Ryūko that she should hand over the Kamui to him and that a Kamui is murderous parasites which kill their user but Ryūko blankly refuses to which he proceeds to kill her, but Senketsu telepathically threatens Tsumugu that if any harm shall befall Ryūko he will kill him, leaving Tsumugu surprised. Nonon Jakuzure arrives with a plan to capture Tsumugu, but Tsumugu uses a smoke bomb to escape taking Ryūko with him. He arrives at Aikurō's house and they talk a bit, while Ryūko thanks Senketsu for saving her tells him that he is her friend making him pleasantly surprised.

Episode 6
The next day Ryūko confronts Aikurō and demands to know how he is associated with the mohawk man who attacked her in the school. At first, Aikurō feigns innocence but after she shows him the picture of him and the man drinking he tells her that the person, Tsumugu Kinagase is a member of the Nudist Beach and that he was sent to fight Ryūko to test her abilities, but Ryūko does not believe his statements and leaves angrily. At the Honnōji Academy club research laboratory, a huge shipment of life-fiber arrives which is being used by sewing club president Shirō Iori to mass-produce Goku uniforms. Athletics club president Uzu Sanageyama requests Satsuki Kiryūin permission to fight Ryūko to which Satsuki says that he will pay a price for his failure in defeating Ryūko. He assures her that he has confidence in his superior eyesight. The next day Ryūko finds a notice from Uzu telling her that he plans to duel with her. Uzu uses his armor the Blade Regalia and his special ability Higi Tengantsu to momentarily overpower Ryūko and does damage to her but she uses Sunketsu's torn piece of cloth to blind his visor, blocking his vision, giving her time to deal a finishing blow, defeating him. Uzu refuses to accept defeat and asks for a rematch resulting in him being bashed by Ira Gamagōri, who calls him a disgrace. After his defeat, Uzu meets up with Ira Shiori, sewing club president and tells him to sew his eyes shut as he relied too much on them resulting in his defeat. He then goes to Satsuki who questions his resolve but is impressed when he shows his sacrifice for his overconfidence. He faces Ryūko again and gets back at her for his current state using Shingantsu an upgraded version of his Tengantsu, viciously attacking her and coming close to killing her only to be stopped by the tearing up of his Goku uniform due to its inability to keep up with his sudden surge of power. Ryūko manages to escape but accepts the fact that the Elite Four aren't show-offs and that they are tough as they come.

Episode 7
Ryūko is attacked by three members of the acrobatic club who have split up and formed their own club so as to raise their star uniform ranking by defeating her. Mako tells her that if a club member forms their own individual club and becomes its president they will rise to two-star status and if they manage to defeat Ryūko they will be awarded a Three Star Goku uniform. Mako also tells her that the more stars they have the more luxury the student is offered, giving Ryūko the idea to start her own club. When Ryūko discovers how much paperwork is involved she makes Mako its president instead much to her reluctance. As the club progresses so does the living and social condition of the Makanshoku's. But the family gets too carried away by its new-found grandeur and they become slaves to their materialistic urges greatly saddening Ryūko who resigns as a member of the Fight Club. But Mako refuses and Satsuki uses the rift caused by their views as a tool to make Mako fight against Ryūko by giving her a Two-Star Goku uniform and telling her that if she wants to keep her social status as it is now she should fight Ryūko and defeat her, to which Mako agrees, shocking Ryūko. The pair battle but Ryūko only defends herself at first, after a while she stops fighting altogether and takes a harsh beating from Mako until her friend finally snaps back to her senses. Mako disbands the Fight Club and the entire Mankanshoku family apologizes to Ryūko for their behavior and she accepts but warns them not to betray her like that again.

Episode 8
Ryūko takes Mako to the ruins of her old house, where she tells her about the circumstances surrounding her father's death. that she was sent off to a boarding school by her father at a young age. Her father stayed busy with research throughout her life and she slowly developed into a delinquent. One day she received a note from her father saying he wanted to talk to her. However, when she arrived she found him impaled by one half of the Scissor Blade. He told her that if she wanted to live a quiet and peaceful life then she could leave right then but that if she wanted to continue his fight then she should take the Scissor Blade and try to find the other half of it. He said whoever had the other half would be his killer. At that moment Ryūko noticed the silhouette of someone pass by the doorway to leave the mansion and she gave chase, leaving her father calling out to her saying he had more to tell her. Outside, Ryūko saw someone jump away and escape as the mansion blew up with her father still inside. Ryūko tells Mako that this was a wake-up call for her as she knew next to nothing about her father before then and decided to find who his killer was.

Finding no further clues in the basement where she found Senketsu, Ryūko and Mako head home, only for their scooter to run out of gas. They end up encountering the Disciplinary Committee chair and one of the Elite Four, Ira Gamagōri, who, having just attained his driving license and taking the week off, offers them a ride home. During their drive, they are attacked by the Automotive Airsoft Club led by Ryōsuke Todoroki, who are targeting Gamagōri's Three-Star Goku Uniform Shackle Regalia. Gamagōri defeats them with ease and returns the girls back to the city where they refuel and the trio part ways with Gamagōri promising to face Ryūko on the day of the Election.

The day of the Election arrives and Honnōji's strongest assemble for the Sudden Death Runoff Election, with only Ryūko and the Elite Four making their way to the top. There, Satsuki challenges Ryūko by defeating each of the Elite Four in exchange for details concerning her father's death, her first opponent being Gamagōri.

Episode 9
As Ryūko awaits the time for her battle against Ira Gamagōri, Aikurō Mikisugi asks her to drop out of the match, warning her that she is not ready to face the Elite Four, which she declines. The battle soon begins, with Gamagōri activating his Shackle Regalia, attacking himself in order to provide the power needed to transform into Scourge Regalia. Ryūko soon learns that the Shackle Regalia also serves as an armor protecting its life fibers. This pushes Ryūko into a corner, as she is unable to damage the Shackle Regalia without powering up the Scourge Regalia form.

Undeterred, Ryūko keeps on attacking, forcing Gamagōri to bring out Scourge Regalia's full power, attempting to forcefully mold Ryūko into a model student. However, Senketsu sets a plan into motion by pulling Ryūko out of her synchronized mode, allow her to use Senketsu's fangs to break into Gamagōri's uniform and destroy it from the inside using a new form, Senketsu Senjin, winning the match. With Gamagōri defeated, Ryūko prepares to face up against her next opponent, Hōka Inumuta.

Episode 10
The Naturals Election finals continue, with Ryūko going up against Hōka Inumuta's Probe Regalia. Inumuta uses his uniform to analyze Ryūko's fighting abilities and anticipate her movements, but Ryūko counteracts this by pushing herself to her limits and attacking faster than Inumuta's sensors can react. Changing his strategy, Inumuta uses Optical Camouflage to make himself invisible, allowing him to assault Ryūko with unseeable strikes and force her to the very edge of the arena.

However, Ryūko counters this tactic by expanding Senketsu's eye and attacking the entire battle arena at once, leaving Inumuta unable to evade. With the Elite Four member immobilized, Ryūko goes for the finishing blow, only for Inumuta to forfeit the match on his own. To Ryūko's bewilderment, Inumuta explains that his primary concern is collecting data, not winning; thus, he chose to forfeit the match to preserve his uniform, which had collected significant data on Senketsu.

Ryūko's next opponent is Nonon Jakuzure and her Three-Star Goku Uniform, Symphony Regalia. To Ryūko's dismay, Nonon's "uniform" is a titanic war machine that attacks her with massive sonic vibrations and a variety of music-themed weaponry. Nonon tips the odds even further in her favor by transforming her Symphony Regalia into a flying configuration - when Ryūko protests that the fighters are not supposed to leave the arena, Nonon explains that the rule applies only for being knocked out of the arena. Ryūko is displeased by what she perceives to be the Elite Four making up rules on the fly.

Unable to get close to Nonon, Ryūko ties a thread to her Scissor Blade and uses it to lasso the Symphony Regalia. Bracing herself with Senketsu's skirt spikes, Ryūko begins tossing Nonon around, relying on Senketsu's Life Fiber-infused defenses to ward off Nonon's attacks. Unfortunately, Nonon turns her attacks on the arena itself, hoping to disqualify Ryūko by forcing her to fall. Ryūko quickly comes up with a countermeasure: have Senketsu reconfigure into the flight-capable Senketsu Shippu. This persistence pushes Nonon's temper to its limit - declaring that the sky is her world, she resumes her attack.

Episode 11
With her smaller and more maneuverable Senketsu Shippu, Ryūko has the upper hand against Nonon in the air and manages to destroy her Symphony Regalia Presto. Grounded, Nonon begins to take a beating from Ryūko who attacks her with her finishing move. However, she was unable to absorb the Life Fibers in Nonon's uniform and the Elite Four member still has another form up her sleeve as she transforms into Symphony Regalia Da Capo. She starts blasting Beethoven's Fifth Symphony out of her helmet, the sheer loudness causes Senketsu's link to Ryūko to weaken as he is unable to concentrate. Sanageyama yells at Ryūko not to lose to Nonon because he wants to be the one to defeat her, Nonon yells at him and asks him whose side he's on. This reprieve allows Ryūko to get up and she begins to block Nonon's blast by changing its frequency into a pure tone that matches the beat of her heart. Senketsu is then able to focus on Ryūko's heartbeat and they are able to blast Nonon's attack back towards her, managing to defeat her.

This leaves only Sanageyama for Ryūko to defeat and they begin their battle in earnest. However, before they are even able to land a single blow, someone lands on the arena between them and says she is the one who will fight Ryūko next. No one knows who the mysterious person is but Satsuki Kiryūin is shocked to see her. She is revealed to be Nui Harime, the Grand couturier of Revocs Corporation and a trusted ally of Satsuki's mother Ragyō Kiryūin. Sanageyama attempts to knock Nui out of his way so he can battle against Ryūko but Nui blocks him effortlessly and proceeds to destroy his Blade Regalia Mk 2 in a single move by pulling out its Banshi Thread. Nui challenges Ryūko and to encourage her to fight she pulls out the other half of the Scissor Blade, revealing herself to be the killer of Ryūko's father, Isshin Matoi. This sends Ryūko into a rage as she prepares to charge at Nui.

Episode 12
Ryūko Matoi attacks Nui Harime who had revealed that she was her father's killer. Ryūko unleashes a barrage of attacks on Nui, who manages to block each one with ease. Nui then tells the story of how she came to kill Isshin, "a friend" sent her to find out what he had been researching and working on and to retrieve it. Isshin revealed the Rending Scissors as his life's work, a weapon that could cut and destroy Life Fibers. He attacked Nui with them but was unable to do much damage, Nui turned his blade on him and stabbed him with the Scissor Blade. Before she could do anymore however, Ryūko arrived and began calling for her father, using this opportunity Isshin took the other half of the Scissor Blades and slashed through Nui's left eye. Enraged, Nui attacked him ferociously and sent him flying into the wall. She then made her escape as Ryūko found her father.

Hearing this story, Ryūko asks why she did it and Nui responds that it was to find Senketsu. Ryūko finally loses her temper and the heat of her blood causes Senketsu to lose control and both are transformed into a hideous monster. Seeing this, Satsuki Kiryūin realizes why Nui decided to visit so suddenly and immediately goes to intervene. She asks the Elite Four to evacuate the school and transforms with her own Kamui, Junketsu to try and stop the rampaging Ryūko. At first, she tries calling out to her to get a hold of herself but to no avail. The two then begin fighting, which causes severe damage to the school grounds, Satsuki is ready to kill Ryūko and prepares to go in for the final blow, stating that someone who was being worn by their Kamui was no match for her. Before she can strike a final blow however, Mako Mankanshoku steps in and successfully manages to get Ryūko to calm down after reminding her of some of the times they had shared. Ryūko reverts back to normal but soon passes out because of the strain she had been put through. With the battle over, Satsuki bans Nui from Honnōji Academy and tells her to leave Ryūko and Senketsu to her and Nui outwardly agrees.

Several days later, Satsuki oversees the repairs being made to Honnōji Academy, as Ryūko who has regained consciousness, steps up towards her. Satsuki notes that she is back on her feet and tells her that if Ryūko has to hate anyone then it should be her and says that she was the one who ordered Nui to get the Rending Scissors from Isshin Matoi and that all the answers Ryūko seeks are with her. Ryūko attempts to challenge her but Satsuki stabs her in the gut and notes that she hasn't recovered fully yet, going on to thank her for her assistance in helping strengthen the Goku Uniforms. She reveals that the Elections were all a ploy to get Ryūko to help her discover the weaknesses in the Uniforms so that they could be strengthened and now she is ready to take over the remaining schools in Japan that were not under her control. She announces the Tri-Cities Raid Trip as the operation that will conquer these remaining schools and it is scheduled to begin soon.

Episode 13
Mako tries to decide whether she wants to go on the field trip or not, torn by her reluctance to fight and her desire to have fun on a free trip. Aikurō Mikisugi comes and asks her how Ryūko has been doing, Mako responds that she hasn't worn Senketsu ever since she returned from school after recovering. They are then met by Shinjirō Nagita of the Newspaper Club who has been banned from the school grounds. He wishes to meet Ryūko and tell her to put on her uniform so she can fight to make a difference. Ryūko tells him she doesn't fight because she wants to and that she won't fight for anyone, then she kicks him out of the house. The next day, Nagita gets in trouble for distributing his outlawed newspaper at Honnōji Academy, Mako also gets in trouble for handing them out and is forced to participate in the Raid Trip as punishment. The Disciplinary Committee chases after Nagita who leads them to the Mankanshoku household where Ryūko is to ask her to help him. The Disciplinary Committee catches him but knocks out Barazō Mankanshoku in the process. This angers Ryūko who, with some encouragement from Senketsu himself, puts her Kamui on again. She finds Nagita being accosted by the members of the Disciplinary Committee and defeats them with ease. However it is revealed that they were just puppets being controlled by Nagita to help him get Ryūko to put Senketsu back on. Nagita reveals himself to be none other than Nui Harime in disguise, she asks Ryūko to show her how much power she draws out of Senketsu.

Afraid of losing control again, Ryūko holds back and is unable to defeat Nui, who uses her Scissor Blade to beat Ryūko and cut Senketsu into pieces. Before she can finish Ryūko off for good however, Satsuki arrives and stops her. Nui leaves and Satsuki takes all the pieces of Senketsu. Aikurō Mikisugi, who had been trying to figure out Nagita's identity, arrives to find Ryūko and sees she still has one piece of Senketsu clutched in her hand. Satsuki asks Shirō Iori to distribute all the pieces of Senketsu to students on the Raid Trip.

Episode 14
Awakening in Mikisugi's home, Ryūko discovers Senketsu's consciousness still lives in the scarf that she managed to hold onto. After learning what had happened to his other pieces, Ryūko heads towards the Kansai region, where Satsuki has begun the Tri-City Schools Raid Trip. As the Elite Four attack the main schools in the tri-city area, Ryūko interrupts each of their raids and recovers the scraps that had been given to some of the students to increase their power before heading to her next destination, eventually reuniting with Mako in Ōsaka. Senketsu notes the ease with which Ryūko was able to take down all the Kamui-enhanced students despite not being able to transform and Mako says it's because she's fired up to get her friend back the way he should be. With nearly all of Senketsu's pieces gathered, Ryūko prepares to face Satsuki, who possesses the final piece.

Episode 15
Ryūko finds Satsuki just as she defeats Kaneo Takarada and starts battling her for the final piece of Senketsu, the Seki Tekkō. Eventually, Nudist Beach makes an appearance in mechs very similar to the one Takarada was using, the Dōtonbori Robo, and Aikurō Mikisugi reveals his true identity to the Student Council. However, they in turn reveal that they were already aware of Nudist Beach's existence and Aikurō's true intentions, as well as the true objective of the Tri-City Schools Raid Trip: to uncover and destroy the Nudist Beach organization, which was hiding behind and offering support to the schools of Kansai.

The Elite Four transform into their Mk.II and Mk.III uniforms and engage Nudist Beach in battle. Meanwhile, Ryūko manages to transform even without the final piece, and manages to wring the Seki Tekkō from Satsuki's hand, at last completing Senketsu. With Senketsu back to his old self, Ryūko is able to give Satsuki a real challenge and she tells Satsuki that she no longer fights for her rage but instead does it to protect her friends and that if Satsuki seeks to destroy everything to get her way then she would stop her. She manages to fight toe to toe with Satsuki, and they eventually reach a draw.

With blades at each others' necks, Satsuki agrees to call off the battle and return to Honnōji Academy with the students, but not before Nonon Jakuzure destroys the Nudist Beach base. Their objective fulfilled, the Student Council returns to Honnōji Academy. Ryūko, Mako Mankanshoku, Aikurō and Tsumugu Kinagase gaze at the destroyed city, and Aikurō tells Ryūko that the time has come at last for her to learn the truth about her father.

Episode 16
Mikisugi takes Ryūko to an undamaged section of the Nudist Beach base, an actual beach, to tell her everything about Life Fibers and her father's mission. Mako tags along, wanting to be by her friend's side no matter what. At the base, Mikisugi reveals that Life Fibers are originally from outer space and that they accelerated humanity's development to take over the planet and cover it in Life Fibers.

Senketsu is in shock at learning what he is but Mikisugi has more to reveal as he goes on to explain that Isshin Matoi made the Kamui specifically for Ryūko and only she can use it to its full potential. He says this is because of Ryūko's unusually high tolerance for Life Fibers that Isshin noticed and he did all this so that Ryūko could foil the Kiryūin's plans. Ryūko is disgusted at how Senketsu is being treated as just a weapon and not a being of his own and takes off her uniform, refusing to let him kill his own kind. Deeming Ryūko and Senketsu to be of no more use, Tsumugu prepares to kill them.

Episode 17
Tsumugu prepares to finish off Ryūko and Senketsu but before he can do so Mako interjects and tells Ryūko to put Senketsu back on, Senketsu also agrees by saying that she'll catch a cold. This manages to calm Ryūko down and Tsumugu backs off. Later on outside, Ryūko and Senketsu talk about what they had just learned and see Tsumugu practicing for combat. Ryūko wonders why he is always so intense and Aikurō Mikisugi tells her it is because his sister Kinue Kinagase who was Isshin Matoi's best assistant died in an accident one day during experiments to make a Life Fiber outfit fit for combat. Her last words to Tsumugu were to let the experiments continue. Dr. Matoi continued his work and finally made Senketsu after splicing his Life Fibers with the DNA from Ryūko's nervous system, Ryūko is shocked at this and asks why he did that. Mikisugi replies that Dr. Matoi said it was to keep her safe.

Ryūko and the others arrive at The Great Culture and Sport Festival just as Ragyō has the Life Fibers begin to devour their wearers and jump into the stadium on Mikisugi's Dōtonbori Robo, which he insists on calling a DTR because he dislikes the full name. As they make their way to Ragyō, they are shocked as a blade suddenly stabs its way through her chest, this is revealed to be an attack from Satsuki who says that she is rising up against the Life Fibers. She continues and says she made Honnōji Academy for the sole purpose of defeating Ragyō.

Episode 18
Satsuki tells Ragyō that she always planned to rise up against her and makes a plea to all the people watching the broadcast of the Festival to burn their Revocs clothing. The Elite Four neutralize Rei Hōōmaru and face off against Nui Harime, to allow Satsuki to finish off Ragyō. Satsuki recalls how her father told her of her mother's plans and that Junketsu would be her wedding dress. She talks about how Ragyō married Soichiro Kiryūin for access to his skills and how she was experimented on as a child but failed to fuse with Life Fibers. Ragyō then attempted to fuse Life Fibers with an even younger child, her newborn daughter. The experiment seemed to have failed however and Ragyō disposed of the child. This left Sōichiro aghast and it was at that moment that he turned against Ragyō and dedicated himself to foil her plans. He secretly retrieved his younger daughter, who was still alive and revealed all of Ragyō's secret plans to Satsuki, showing her Junketsu and calling it her wedding dress. He fled from the Kiryūin Manor but Takiji Kuroido went after him and attempted to assassinate him, Sōichiro faked his death and managed to escape with his daughter, changing his identity to Isshin Matoi.

All this while, Ragyō had recovered from the injuries inflicted on her by Satsuki because of her being infused with Life Fibers. Satsuki attempts to finish her off but Rei Hōōmaru intervenes and distracts her long enough to allow Ragyō to escape Satsuki's trap. She then Mind Stitches all the students of Honnōji Academy to attack Satsuki, even managing to Mind Stitch Ryūko. Satsuki attempts to snap her out of the mind control and Ryūko manages to get a hold of herself and escape Ragyō's influence. The two then split up with Ryūko fighting Nui and Satsuki facing off against Ragyō. Ryūko manages to achieve true Life Fiber Synchronization with Senketsu and overpowers Nui. Satsuki chops off Ragyō's head but a single Fiber still connects her head to her body and she is able to regenerate. She tells Satsuki she was never able to bring out Junketsu's true power. Satsuki attacks her but she blocks it, snapping the Bakuzan in two and proceeds to strip Satsuki of Junketsu and wears it herself. Upon seeing how well Ryūko uses Senketsu she becomes intrigued and faces her, pulling her heart out, showing that it is infused with Life Fibers. To everyone's shock Ragyō then states that this proves Ryūko is her second daughter.

Episode 19
As Ragyō shocks everyone with the revelation that Ryūko is her long lost second daughter, Ryūko chops off her hand and puts her heart back in. Ragyō claims that as irrefutable proof of their relationship, claiming that such a strong compatibility with Life Fibers can only be hereditary. Meanwhile, while attempting to evacuate the citizens from the stadium, Mako gets absorbed by the COVERS. Satsuki resorts to her fail safe and causes Ragyō Stadium to self destruct.

A month later, Ryūko is comatose in the Nudist Beach base at Ōsaka. Ragyō sends some COVERS to attack Ōsaka, where Gamagōri tries out a new weapon that extracts humans out of COVERS, he manages to rescue Mako after Guts sniffs out the COVER she was in. The other COVERS create a cacophony and wake Ryūko up who destroys them instantly with her Scissor Blade but refuses to put Senketsu on and says she doesn't want anything to do with him anymore.

Episode 20
After Ryūko expresses her resentment towards Senketsu, Mako confronts her and says that she is no longer being herself. Ryūko responds by saying that she is in fact no longer the same after finding out the truth about her parents and her Life Fiber-infused body. Ryūko is interrupted by Nui Harime and Ragyō Kiryūin, who appear as remote-controlled body doubles composed of Life Fibers.

Nui and Ragyō invite Ryūko to face them at Honnōji Academy. Aikurō Mikisugi warns Ryūko that it's a trap, but she doesn't listen and destroys his DTR. She tells him that she's tired of following him around, and how she hates him for not telling her the truth about her past all along. Mako tries one last time to get Ryūko to wear Senketsu, but is not able to do so. Aikurō tries to follow Ryuko to explain that he did not know the truth about her past, but is stopped by Tsumugu Kinagase. Ryūko leaves to Honnōji Academy on a motorcycle.

At Honnōji Academy Ryūko fights Nui. After a while, she's able to outpace Nui's movements and stab her in the heart with the Scissor Blades. Nui pretends for a while to be struggling in great pain, but eventually reveals that she's also infused with Life Fibers and actually capable of regenerating. Nui also reveals that, after Ryūko's supposed death as a baby, she was created by Ragyō in an artificial uterus made of Life Fibers, as part of her third attempt of making a Life Fiber-infused human.Ryūko is then surprised by Ragyō, who presents her with a modified version of Junketsu. Ryūko is constrained by Life Fibers sewn into her skin by Nui during their fight, and forced to wear Junketsu. Her memories are altered by Ragyō so that she is now loyal to her.

At the Naked Sun 1, Satsuki rests after successfully escaping from Honnōji Academy in the chaos of Ryūko's arrival and enjoys a cup of tea made by Mitsuzō. The ship's radars detect an unknown object incoming at high speed. A light blue ball of light collides with the ship's deck causing minimal damage to the ship, and is revealed to be the now brainwashed Ryūko, wearing Junketsu. Tsumugu attempts to face her in his prototype upgraded DTR, which is more powerful than the original one she destroyed, but is quickly defeated. When Ryūko is about to kill Tsumugu, Satsuki appears, now wearing Senketsu, and challenges her to a fight.

Episode 21
Ragyō and Nui successfully brainwash Ryūko and she transforms with Junketsu. It is revealed that the Life Fibers inside Nui repel all other Life Fibers and that is why she is unable to draw any power out of Kamuis which is why she chose to make them instead. Before leaving after Satsuki, she kisses Nui for good luck and Ragyō leaves for REVOCS Corporation, taking the officials to be absorbed by the Original Life Fiber, which then transforms into a giant airship made entirely of Life Fibers.

At the Naked Sun, Ryūko and Satsuki begin their face-off and Satsuki uses both of Senketsu's forms, Senjin and Shippu during the course of the battle to throw Ryūko off guard. She also uses a combination of both forms to attack her. Though ultimately Ryūko is too powerful to be kept down for long. She begins to overpower Satsuki and gives her a brutal barrage of attacks, slicing Senketsu off of her. The Elite Four rush in and trick Ryūko into a range of Gamagōri's extraction weapon. They are unable to extract her however, as Nui Harime intervenes and reveals that Junketsu was stitched onto Ryūko and that trying to remove it from her would kill her from the shock.

Mako attempts to reach out to her friend and save her saying she is still the same Ryūko. Nui finds this annoying and tries to kill Mako, who is saved by Senketsu who forces her to wear him. Satsuki engages Nui in combat and during their fight, she claims that they will be victorious as Nui has still kept her half of the Scissor Blade and that shows they are still unsure of Ryūko's loyalties, Nui becomes agitated at this and her reaction assures Satsuki that her theory is correct. The Elite Four once again barge in to distract Nui and Satsuki goes after Ryūko, slicing open Junketsu so that Mako can throw Senketsu into it and free Ryūko. Mako is also absorbed alongside Senketsu and they both manage to bring Ryūko back to her senses. They are ejected out of her and Nui believes that they failed and asks Ryūko to help her destroy the ship, before she can do anything though, she is impaled in the chest by the other half of the Scissor Blade and sent flying. Ryūko proceeds to tear Junketsu off her herself and causes a shower of blood in the process, saying that it's the only way she can wear Senketsu again.

Episode 22
Ryūko successfully rips Junketsu off of her body without dying. She reunites with Senketsu and fights against Nui Harime, recovering both Scissor Blades. When Nui tries to stab her through the throat, Ryūko gets behind the Grand Couturier and chops her arms off. Although Nui puts on a show of pain and anger, the facade soon becomes real panic when Ryūko destroys the arms, severed thanks to the Scissor Blades. An enraged Nui is rescued by Rei Hōōmaru, to the former's anger; while Ryūko's allies deal with the COVERS, extracting the School Club presidents and gathering the Life Fibers left behind.

Afterwards, Ryūko tells Satsuki Kiryūin that she will punch her full force to determine if she's worthy of fighting alongside her against Ragyō. Satsuki accepts the challenge but Ryūko is unable to get a hit in as the Elite Four block her attempts and tell her that they won't let her touch Satsuki while they're around. Ryūko realizes that Satsuki has people looking out for her the same way Mako and Senketsu do for herself and allows Satsuki to join her for the battle against Ragyō. They all prepare their battle plans, which is to stop Ragyō from taking the Original Life Fiber to Honnōji Academy and using it to send a signal to all the other Life Fibers to devour the planet. They are attacked by missiles and Ryūko and Satsuki both prepare to protect the ship, Mitsuzō Soroi asks "Lady Ryūko" to protect her sister and she agrees though is flustered at having to call Satsuki her sister. Satsuki uses a modified Junketsu which is able to take a new form capable of flight after being infused with Life Fibers from Senketsu. She calls the new form Senketsu Senpu and along with Ryūko in Senketsu Shippu, both sisters protect the ship from the missiles. A giant COVER rises from the ocean in front of the Naked Sun but is met with Mako who has her old 2 Star Goku Uniform back.

Episode 23
Ryūko and Satsuki, reassured now that Mako is defending the Naked Sun, continue on their flight to the Original Life Fiber and Ragyō. They arrive and begin to attack her but she pulls out dual needle blades of her own from the Original Life Fiber and blocks her daughters' attacks. Ragyō explains that both the Bakuzan and the Rending Scissors were based on the needle blades and then she begins to fly herself and attacks her daughters. They are no match for her and as Satsuki steps onto the Original Life Fiber Ragyō immediately rushes to kick her off, saying the Original Life Fiber was not meant to be stepped on, having herself stood upon it with a tissue instead of having direct contact with it. Ragyō then directs the Life Fiber towards the Naked Sun so it can absorb the ship's crew. Ryūko devises a plan and signals it to Satsuki, who understands and nods. Ryūko then charges towards Ragyō with both her Scissor Blades to perform her finishing move but before she is able to complete it Ragyō stabs her with both her blades and slices her in half, throwing her into the sea. Mako sees this as she is defending the ship and is left distraught. Suddenly, more COVERS appear and catch her off guard but at that moment Shirō Iori drops the Elite Four's now completed new Three Star Goku Uniforms and they all transform into their Ultimate Battle Regalia. Using their combination special move "Utter Victory", they defeat all the COVERS at once, leaving Mako impressed though Tsumugu believes they were being too flashy.

Satsuki continues her fight with Ragyō, enraged at what she did to her sister but is quickly disarmed by Ragyō who grabs her by the throat. She tells Satsuki that they had only gotten that far because of Ryūko and the powers she held due to being infused with Life Fibers. Saying that since Satsuki wasn't infused with Life Fibers, then she and her "makeshift Kamui" wouldn't be able to beat her. Satsuki accepts that she may be a fraud but even so Ragyō would pay if she underestimated her. Suddenly, Ryūko bursts out of the sea and begins to attack the Original Life Fiber, leaving Ragyō shocked. Satsuki frees herself from Ragyō's grip and clacks her heel on the Life Fiber, saying this was all part of Ryūko's plan, where she blocked the needle blades just enough to protect some her Life Fibers to be able to regenerate underwater and be in the perfect position to attack the Original Life Fiber. Ryūko makes her way to the core of the Life Fiber and opens her Scissor Blades to dual decapitation mode to destroy it but struggles to cut through it. Back at the Naked Sun, Aikurō converts the ship to it's closed form, which resembles a seam ripper and attempts to charge at the Original Life Fiber with it while the Elite Four assist Satsuki in fighting Ragyō and keeping her busy. With the ship's turbines not moving fast enough for it to cause any significant damage, Mako suddenly steps up and starts running a turbine with all her might so that she is able to help her friend and manages to give the ship a huge boost and lets it cut straight through to the core where Ryūko is. She is shocked to see the ship, being powered by Mako come all this way and upon her friend again becomes fired up and with the help of the ship manages to cut straight through the Original Life Fiber, with the Naked Sun ramming straight into the side of Honnōji Academy. Ragyō is surprised and angered that the Original Life Fiber was destroyed and retreats to Honnōji Academy saying that it is not yet over. Everyone takes a break and has some of Mitsuzō Soroi's tea, then Satsuki and Ryūko prepare for the final battle.

In the post-credits, Nui shows up, looming comically large over the Academy as she presents the now completed Shinra-Kōketsu to Ragyō who puts it on and prepares to finish off her daughters.

Powers and Abilities

 * Natural Abilities:
 * Super-human power: Ryūko's strength, speed, and abilities far surpass that of an ordinary human. From the start, Ryūko was able to take on multiple One-Star students by herself, without the need to wear Senketsu, as seen in episode 1. She became much stronger throughout the series, both on her own and in her synchronization with Senketsu. Even while wearing a scarf with only Senketsu's eye sewn to it, she was still able to defeat numerous students with new Goku uniforms enhanced by fragments of Senketsu with ease while riding on a motorbike. Her power has increased further when she comes to terms with her true nature as a life-fiber hybrid and thus stops thinking of herself within the bounds of human limitations. In her rage at finding out she is not human she was able to destroy multiple COVERS and free the humans therein with one swing of her scissor blade in episode 20, and also sliced several buildings apart from afar with one blow, all without Senketsu.
 * Life Fibers infusion: Ryūko is revealed as Ragyō Kiryūin's second child whose body had been infused with Life Fibers, despite it being perceived as a failure by Ragyō then. It is likely that her incredible potential and her natural ability to synchronize with Life Fibers was a result of this. Ryūko has also demonstrated resilience and superhuman healing on par with Ragyō herself. An example of this is shown when her heart is pulled out her chest by Ragyō; the heart is simply drawn back into Ryūko's body automatically and the wound seals itself.

Former Powers and Abilities

 * Scissor Blade – Ryūko's signature weapon is one half of a giant pair of scissors, which she wields as a one-handed, single-edged longsword. The blade is capable of cutting Life Fibers, which are otherwise indestructible. Ryūko alternatively uses it as a makeshift tennis racket during her match against Omiko Hakodate. She obtains the second half of the Scissor Blade after snatching it from Nui Harime in Episode 22.
 * Decapitation Mode – While using Life Fibers Synchronize, Ryūko can mechanically extend her Scissor Blade into a two-handed sword. Not only is the blade's length doubled in this form, but its strength increases exponentially and is able to slice far beyond its normal range. This ability is frequently used in preparation for a Fiber Lost.


 * Kamui Senketsu
 * Life Fibers Synchronize
 * Fiber Lost – After Ryūko defeats her opponent, she destroys their Goku Uniform, allowing Senketsu to absorb the uniform's Life Fibers, adding them to his own power. The Banshi is always the last one to go. "戦維"(sen'i) is a compound word of 戦意 (fighting spirit, sen'i) and 繊維 (fiber, sen'i).
 * True Life Fibers Synchronize – After Ryūko invades the Great Culture and Sports Festival and fights Nui once more, her original Life Fiber Synchronize evolves thanks to her own self-improvement and she becomes completely one with Senketsu. In this state, Senketsu glows with intense power and they reach levels of strength and speed that easily overpower Nui Harime. After the final battle against Ragyō and Shinra-Kōketsu, Senketsu manages to send Ryūko back to Earth before he disintegrates completely.


 * Kamui Junketsu
 * Life Fiber Override - Ryūko is forced to put on Junketsu by Ragyō, which alters her memories, making Ryūko believe that she had been raised lovingly by Ragyō her whole life. As Ryūko is a human fused with Life Fibers, Ragyō believes that Ryūko, unlike Satsuki Kiryūin, is able to draw out its maximum power. Its appearance varies from Satsuki's version in that Ryūko's chest is covered, while she wears a hakama on her lower body. The back parts of her hair are now colored blue, although she retains the red highlight on her fringe. After Mako and Senketsu's final efforts to free her, Ryūko returns to her former self and rips apart Junketsu.

Senketsu
At first, Ryūko was embarrassed to wear Senketsu due to the rather revealing appearance of his transformed state. However, she understands later on that the only way to be able to use Senketsu to his full potential is to wear him proudly and be open to him. Ryūko cares for Senketsu and considers him a dear friend, even to the point of saying that if Senketsu were to be taken from her they would have to pry him from her cold dead fingers. She was also very concerned when Senketsu was being washed very roughly by Mako's mother. Originally, she decided never to wear Senketsu anymore because she feels that she is a Life Fibers monster herself. After coming to her senses and separating herself from Junketsu, she has rekindled her bond with Senketsu.

Mako Mankanshoku
After Ryūko enrolled into the academy, Mako quickly became attached to her. At first, Ryūko felt slightly uncomfortable by Mako's excessive attachment, but with time the two grew to care a lot for each other and quickly became best friends. Mako is always cheering for Ryūko during her fights, and, as Senketsu cleverly noted, is the key to get Ryūko to relax. Prior to Ryūko's final battle, Mako asks her on a date, and Ryūko is seen holding the promise as motivation to keep fighting. They are later seen going on that very date with Satsuki as company as the credits roll.

Aikurō Mikisugi
While Ryūko does not yet seem to trust him completely, Aikurō seems determined to help her uncover the truth behind her father's murder. He is also constantly watching her fight from behind the scenes, always on high alert should something go wrong. He is shown to be especially concerned about Senketsu's fast evolution. When in Ryūko's presence, he has a tendency to show off his well built body. This flusters her and makes her uncomfortable. Aikuro has notably shown hesitation in any case of disposing of Ryūko as suggested by Tsumugu Kinagase, even when Ryūko lost control and was consumed by her Kamui, hesitating in shooting her and alerting her berserked form to his presence.

Satsuki Kiryūin
Ryūko and Satsuki had a strong mutual dislike initially, mostly due to Satsuki withholding information about her father's murder. While they seem to respect each other a bit more after their fight in Osaka in episode 16, her hatred for Satsuki is challenged near the end of episode 17, when Satsuki reveals her coup d'etat behind her mother's back in order to take revenge for her father and baby sister, thought to have been disposed of after a failed attempt to fuse her with Life Fibers. When it is revealed that Ryūko is actually that sister but had actually survived and successfully fused with Life Fibers, by episode 22, Ryūko and Satsuki have come to good terms with each other and team up to defeat Ragyō and the original Life Fiber. Eventually, Ryūko and Satsuki fully accept each other as sisters and are shown to love each other, much to the confusion and heartwarming of the rest of the cast.

Uzu Sanageyama
Sanageyama's initial rivalry towards Ryūko was a result of her having continuously defeated several sports clubs that were under his supervision. Confident that he could beat her with his Tengantsu, he was the first Elite Four to openly challenge her but a tactic that stripped him of his Tengantsu defeated Sanageyama and left him in utter disgrace. Determined to defeat Matoi and win back his lost pride, Sanageyama sewed his eyes to become stronger for his second battle. However, as his uniform overheated from his power before he could deal the finishing blow, Matoi managed to escape, leaving Sanageyama ashamed once more, despite Satsuki's assurance. As a result, he looked forward to finishing their fight at the Naturals Election. Unfortunately, he was denied this chance by Nui's interference. By that time, he found Matoi worthy of respect, calling her "the woman who took his eyes (Tengantsu) and gave him the world (Shingantsu)".

Nui Harime
Ryūko has a strong hatred towards Nui, especially due to her being the killer of her father. Ryūko was especially angry to see her, which eventually causes her blood to boil so much that she made Senketsu go Berserk. In Episode 13, however, Ryūko instead fears of seeing Nui again due to her fear of going into another rampage, which might lead to her death. In Episode 22, after being released from being brainwashed, Ryūko cuts off Nui's arms and absorbs its Life Fibers, which leads to Nui losing her cutesy demeanor and swearing revenge. In addition, by this point her hatred toward Nui had cooled into more of an annoyance, which maddens Nui even more as she had previously thrived on Ryūko's hatred of her and makes her hateful toward Ryūko now.

Ragyō Kiryūin
Head of the Revocs Corporation and Satsuki's mother. When they finally meet in Episode 17, Ryūko scorns her for her self boasting. This disdain, however, turns into seething rage when she learns not only that Ragyō is her mother, but that she has been fused with Life Fibers as a baby at her very hands. After Ragyō's defeat, though, Ryūko does show some consideration for her, and attempts to get her to surrender peacefully but Ragyō chooses to pull out her own heart and would rather commit suicide instead of returning to Earth with Ryūko.

Junketsu
In Episode 20, Ryūko fell victim to Ragyō's trap and was "worn" by Junketsu, Satsuki's former Kamui. While being worn by Junketsu, Ryūko's personality underwent a complete reversal: she became battle-crazed and bloodthirsty, turning against her own allies. Additionally, her strength and speed increased dramatically. After the mental control was dispelled, Ryūko felt furious and disgusted for having been forced to wear Junketsu, promptly and forcibly tearing it off.

Memorable quotes
"I finally get it now. I need to get naked. Putting on a Kamui means becoming one with you! It means you becoming one with me! That's what it means to master wearing you! Isn't that right, Senketsu?!"

- Ryūko finally accepts Senketsu

"Blow it out your ass, bitch! It's gonna take a hell of a lot more than you to stop me!"

- Ryūko's response during her fight against Nonon Jakuzure

"Are you kidding?! That freakin' hurt! But I guess I had it coming after acting like such a dumbass!"

- Ryūko, after she forcibly tears off Junketsu

Trivia

 * The name Ryūko means "flow, style, manner, method" (流) (ryū) and "child" (子) (ko). Incidentally, it can also be derived from "fashion, trend" (流行) (ryūkō).
 * Ryūko's surname Matoi means "wear, wrap, tie, follow around, collect" (纏).
 * Ryūko's unique gear-like pupils (and likely her single red highlight) are very likely side effects of her infusion with Life Fibers.
 * They're also possibly a reference to a character from the creator's previous work, Gurren-Lagann, in which Nia Teppelin had flower-shaped irises, which are further a reference to Nono from Diebuster.
 * The back of Ryūko's casual jacket, only seen at the beginning and end of the series, also resembles the look of the Team Dai-Gurren logo.
 * She had a black shirt with the same skull design as her jacket when she was younger.
 * According to Shigeto Koyama, in the early concept designs for Ryūko, she had long black hair and an overall physical appearance similar to Satsuki Kiryūin. The fact that Satsuki briefly wears Senketsu later on in the series was a nod to Ryūko's original design.
 * Studio Trigger outsourced the 12th episode of Yama no Susume and added a cameo of Ryūko as a student. There were some slight appearance differences like her red streak being noticeably blacker compared to her hair and her eye design to look more like other students.
 * In the 2019 anime film, Saekano the Movie: Finale, a figurine of Ryūko dressed as a bunny girl can be see on the top of Tomoya Aki's figurine shelf. Both Saekano and Kill La Kill share the same anime distributor, Aniplex.