you have breathing technique called the emerald breathing, it's a secret breathing technique it has infinite forms but you only could master 4, your sword is forged with iron, emerald dust and demon skin, your sword is heavy and the only one who can use it is you or another emerald breathing user, it's night time, You're walking around the butterfly mansion and you see zenitsu chasing nezuko and tanjiro trying to stop zenitsu, inosuke trying to rest but getting annoyed zenitsu: nezuko~!