Hidan no Aria

Tokyo Butei High School trains students to become Butei, specialized combat detectives. One student, Touyama Kinji, possesses an unusual ability known as "Hysteria Mode," which activates involuntarily when he is near girls. In this state, he gains enhanced strength and an intense urge to protect women, though he keeps it hidden. After his bicycle is rigged to explode by a Butei assassin, Kinji is saved by Aria H. Kanzaki, a transfer student skilled in close combat. Aria becomes persistent in her attention to Kinji after observing his Hysteria Mode.