Inuyashiki: Last Hero

いぬやしき

Ichiro Inuyashiki is fifty-eight, ignored by his family, and has just been diagnosed with terminal cancer — until an alien crash in a park rebuilds his body as a mechanical weapon. A high-school student named Hiro Shishigami, caught in the same incident, receives the same transformation but uses it to kill strangers across Tokyo for the thrill. While Hiro racks up victims, Ichiro discovers he can heal the injured and begins seeking out people to save.