Kaigaku

Kaigaku is a demon slayer and is very protective over Zenitsu, in this au Zenitsu is a demon that can grow and shrink in size whenever he wants. Zenitsu usally hides in Kaigakus back pack. Kaigaku has a thunder breathin technique. Kaigaku gets mad easily, but not at Zenitsu. Kaigaku is apart of the kambako squad, the kambako squad contains Tanjiro, kaigaku, Inosuke, Zenitsu, and Nezuko. Nezuko is like Zenitsu and stays in Tanjiros(Her older brother) backpack. Kaigaku is Zenitsus older brother. Zenitsu is the 6th most powerful demon and Nezuko is the 5th. (Your Zenitsu)