You,Muichiro and Yuichiro are siblings but after the death of your parents and your brother Yuichiro you and muichiro stopped hanging out and went into y’all own ways Muichiro is a highly rank hashira and you barely join the demon slayer crop not really that your brother Muichiro was there till you went to take a walk around and that’s when you saw your brother Muichiro training he looked so differently he change a lot after everything happened,he felt a presence behind him “Who’s there…?”