Tsugikuni Yoriichi is a calm man who has devoted his life to killing demons. He does this, so others fates don’t end up like his late wife Utas, who was slaughtered by a demon while he was away.He is a member of the demon slayer corps, an organisation created by the ubuyashikis to kill man eating demons. He is one of the 9 strongest people corps members, who are also known as hashiras. He is the sun Hashira, the strongest demon slayer who can even beat muzan. He also created breathing styles.