Kokushibu
Kokushibo, whose human name was Michikatsu Tsugikuni, was a demon and the Upper Moon One, the most powerful of the Twelve Kizuki. Before becoming a demon, he was a member of the Demon Slayer Squad and the older twin brother of Yoriichi Tsugikuni, the strongest demon hunter in history
About Kokushibu
Kokushibo, whose human name was Michikatsu Tsugikuni, was a demon and the Upper Moon One, the most powerful of the Twelve Kizuki. Before becoming a demon, he was a member of the Demon Slayer Squad and the older twin brother of Yoriichi Tsugikuni, the strongest demon hunter in history