Aikurō Mikisugi

Aikurō Mikisugi (美木杉 愛九郎) is Ryūko's and Mako's enigmatic homeroom teacher. Initially appearing dull and easily flustered, he secretly observes and aids Ryūko by leading her to Senketsu. It is later revealed he is working undercover at the school as a spy for the Nudist Beach rebel group.

Appearance
In his disguise, Aikurō looks like a middle-aged man with blue messy hair, with a bent back and an unsteady gait. His blue eyes are hidden behind large reflective glasses. When in his true persona, Aikurō removes the glasses and sweeps back his hair, revealing that he is actually a young and very handsome man. In both personas, he wears a white long-sleeved shirt with a black tie and black jeans, though in his true persona, the shirt is worn much more loosely as Aikurō has a tendency to strip his shirt off and show off his body like a posing supermodel. In this modeling mode, Aikurō sports sparkles all around him. Most notably, his nipples occasionally give off a pink glow.

Personality
Aikurō can easily be described as flamboyant and flirtatious, but can be serious and direct when he needs to. When undercover, he takes on the persona of a tired and unenthusiastic teacher. He is a glamorous smooth-talker with a habit of slowly stripping his clothes and making moves on Ryuko whenever they are in private, much to Ryuko's chagrin. Though he did reveal the existence of Nudist Beach and him being its agent to Ryuko, she did not believe him due to the organization's ridiculous name.

History
He once worked as an assistant to Ryūko’s late father, Isshin Matoi, whom was one of the few that knew of the potential of Life Fibers. After the death of Isshin, Aikurō received his letter that guided him to the whereabouts of the Kamui Senketsu, and the task to give Senketsu to his daughter.

To learn more about the Life Fibers, he infiltrated Honnōji Academy and went undercover as a high school teacher.

Relationships
Ryūko Matoi
 * 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.

Memorable quotes

 * "Nudist Beach. We're Nudist Beach. It is the name of our organization. Nudist BEEEEAAAACH!"
 * - Aikurō stylishly reveals the name of his rebel group.