Kinji Tooyama would rather stay invisible at Tokyo Butei High, a school that trains armed detectives, than let anyone learn about Hysteria Mode, a power that flips him into a hyper-competent fighter under stress. When a bombing incident exposes that power to Aria H. Kanzaki, an S-Rank ace and descendant of Sherlock Holmes, she declares him her partner whether he agrees or not. Chuugaku Akamatsu's original light novel remains ongoing and is the basis for the manga and TV anime.