Hidan no Aria

As violent crime grows, Japan trains armed detectives known as Butei at Tokyo Butei High School. Kinji Tooyama once belonged to its elite Assault Division, but he now avoids combat and hides a peculiar ability that transforms his fighting skill whenever his emotions are pushed in an embarrassing direction.

His quiet escape from danger ends when the notorious Butei Killer targets him. Kinji survives only after crossing paths with Aria Holmes Kanzaki, a brilliant, heavily armed top-ranked Butei. After witnessing what Kinji can really do, Aria refuses to let his talent go to waste and insists that he fight at her side.