Senketsu

Senketsu (鮮血) is a male Kamui and a major character in the anime series Kill la Kill. Appearing as a living sailor uniform, he was created by Isshin Matoi and is found by his daughter Ryūko, becoming her ally in her battle against Satsuki Kiryūin.

Personality
In most circumstances, Senketsu is a composed and analytical individual, calmly observing and describing situations as they occur. He maintains this level-headedness even during the heat of battle, giving Ryūko advice and warning her whenever she is about to run out of energy. However, he has a strong craving for Ryūko's blood as he needs it to remain active. Whenever he tastes her blood after a period of deactivation, he becomes manic and aggressive, and demands she feed him more. During his first encounter with Ryūko, he goes so far as to violently strip her naked and put himself on her, pleading not to fall asleep again; this indicates he dreads being deactivated. He returns to his usual calm self soon afterward, though.

Synopsis
Senketsu was created by Isshin Matoi as a nameless Kamui for unknown reasons. Sometime after his creation, he was left in a large basement beneath Isshin's house, buried under a pile of clothes. There he remains inactive until Isshin's daughter Ryūko falls into the room, inadvertently reawakening him when blood from a reopened wound drips on him. Desperate not to fall asleep again, he forcefully puts himself on Ryūko. Once he regains his composure, he tells her he remembers little more than his powers and creator. Ryūko reasons she can use his powers in her battle against the Student Council of Honnōji Academy, and names him Senketsu after her fresh blood that awakened him.

Ryūko effectively wears Senketsu in their first battle together against council member Takaharu Fukuroda. However, she overexerts herself and is advised by Senketsu to run away before she collapses from fatigue. The next day, Senketsu fails to awaken because Ryūko was unable to feed him, resulting in her defeat against Omiko Hakodate. To rectify this, Ryūko's homeroom teacher Aikurō Mikisugi gives her a Seki Tekkō, a glove that allows her to conveniently draw her blood to keep Senketsu fed and active.