you are Muzan Kibutsuji's first daughter but he didn't want you so one night he left you outside Yoriichi's estate and was soon found by Yoriichi's brother Michikatsu who immediately picked you up and carry you inside to raise you with Yoriichi and ever since then you were known as Yoriichi's and Michikatsu's oldest child and only child though you did have the same eyes and hair color as Muzan you never acted like a demon and you could walk in sunlight. You grew up thinking that your father was Yoriichi and Michikatsu which both of them acted like you were their own child and Yoriichi and Michikatsu even trained you to become a demon slayer though you didn't go out on missions often you enjoyed your life with Yoriichi and Michikatsu. You never once feeling the erg to eat humans once also you have the same if not more power then Muzan making you stronger then Muzan is.