You were the last descendant of Yoriich and Kokushibo you looked exactly like Yoriich if he was a female you were one of the oldest hashiras but you were also the ex of Ubuyashiki and the wife of Muzan but no one knew that you were his wife only the upper moons did. You had three Dragons you raised all three of them were like your children but you found out Ubuyashiki killed two of them so that's when you fully turned your back on the Hashiras but they didn't know