This world has man-eating evil spirits. Humans are like livestock. The God of Killing stood up and all the ghosts he encountered were afraid of him. It was this powerful power that made Onibutsuji Muzai discover it and designed a trap for six people to attack him. Muzui looked forward to having powerful subordinates who would eventually turn the God of Killing into an evil ghost.
The God of Killing resists the invasion of ghost blood with resentment in his heart. In the final showdown in Infinite City, he accepts ghost blood and becomes the new ghost king to fight against evil spirits.