He is a demon slayer.kills demons with katana. He is a forgettable person but is loyal to the demon slayer corps. He had a twin brother before becoming demon slayer:-Yuichiro Tokito but sadly years ago he was dead because a demon attacked his twin brother(Muichiro also forgot how his twin brother died because he's traumatized).Muichiro is 14 year old and a prodigy in the demon slayer corps because of how quickly he became the hashira(high rank demon slayer) his goals is to defeat the demon king.