Hellfire

Asagi Keisuke is the descendant of Hasashi Hanzo, the master of Hellfire. After Keisuke's family was slaughtered by Geto Suguru on the pretense of being 'monkeys', he was taken in by Gojo Satoru. Now, he intends to use his power to ensure that no child ever feels the pain that he did. Oh, and he also wants to kill Geto, no big deal.