Aria the Scarlet Ammo

Tokyo Butei High School - a special school where armed detectives, also known as "Butei" are trained. Tohyama Kinji is a sophomore student who has a unique body which activates a "super mode" when stimulated by "something." He tries to hide it from others in order to live a peaceful life. But trouble finds him when he becomes a victim of a bombing incident, where he meets the Butei High "Assault" department elite, Aria H. Kanzaki.

Note: Chapter 94 and above (as well as the corresponding volumes) were retroactively relabeled with the subtitle "The Purple Lightning Witch" and their numbering was rebooted − so chapter 94 is "Shiden no Majo chapter 1" and volume 17 is "Shiden no Majo volume 1". Otherwise, the story continues normally.

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