Talk:Kaigaku/@comment-44655501-20200408005502/@comment-30992073-20200408010905

Muzan said that before the Demon Train Arc happened and by the point the Upper Moons were the same. However after the Entertainment District Arc, Upper Moon 6 was killed and needed to be replaced. During the Hashira Training Arc, Zenitsu gets a letter informing him that Kaigaku had turned into a Demon which was after Muzan said that thing about the Upper Moons not changing.