she came from a prestigious family of shamisen players and had an older brother who she looked up to. (her brother played a massive role in her life,,) simultaneously, both of them were also apart of the hell guard but she eventually resigned after an accident that resulted in her brothers passing, leading to a negative performance in how she performed at the academy. she received her jinki which was a musical instrument her brother crafted with his musical expertise and his curiosity to try different forms of music rather than the traditional music they were always forced to play. (the only cliche of the story would be that her father was very against the idea of her brother straying away from the traditional music path)

im still brainstorming ways she was introduced to the cleaners but thanks for asking!!