Webkokushibo ( kokushibō?) is a major supporting antagonist of demon slayer: He is a demon affiliated with the twelve kizuki, holding the highest position,. Webthe history of kokushibo takes us back to the sengoku era, which was known as the golden era for the demon slayers. He was the elder brother of yoriichi. Webkokushibo's name derives from the japanese word for the black death. He is one of the few demons who clearly remembers their past lives as human beings, including their. Webout of lust for power and the fear of death, michikatsu became a demon and took on the name kokushibo. Because he was also a breathing user, it took him three days to fully.
