Haru is a fellow high school student and a friend of Akiyuki's, and fairly skilled in martial arts. She is the first to encounter Xam'd on the destroyed bus, and later realises the connection between Xam'd and Akiyuki. She later joins the South Eastern Autonomy, and becomes a Mainsoul. She then deserts and goes to Akiyuki, helping him remember his name(after he lost his memory).
After Akiyuki's disappearance, Haru made a promise to return his arm band to him.