Momoko's roommate. He first meets Momoko when he saves her (while she was a girl) from getting hit by a car. He calls her stupid for not paying attention and she returns that he is a bastard. After discovering that she is a girl, he initially attempts to black mail her into being his slave. Over time his feelings change, and he considers her as a precious person. He repeatedly saves Momoko, and declares his love for her after rescuing her from Yousuke's attempt to blackmail her into being his girlfriend. He is caring, kind, and sometimes possessive or jealous when it comes to his girlfriend. At the end of the series, he lets Momoko leave the school to start again as a normal girl, though it is only a brief goodbye, as they will always remain as "one."