He is a former Jujutsu Sorcerer and was partner of Satoru Gojo before betraying Gojo. He began to develop a deep hatred for all non-sorcerers, planning to create a world consisting only of jujutsu sorcerers and curse users. He was the orchestrator of the Night Parade of a Hundred Demons, a jujutsu terrorist attack on the cities of Kyoto and Shinjuku. Eventually, his body was taken over by Kenjaku after his death.