Since there were no warnings for the chapters:
TW: Some scenes in different chapters depicts graphic abuse and violence, and in some cases s3xual harrassment. Mentions of r@pe as well, and a one-sided inc*st from the disgusting brother fantasizing about his sister s3xually. Please be warned.
This is a story about Nullitas, the illegitimate child of the Count who was born from him forcing a servant (Nullitas' mother). Nullitas lived most of her life as a boy due to her mother fearing she'll have to go through the same thing as her mother did; that is, until the Emperor decreed for the Duke and the Count's daughter be married off. Not wanting his daughter to be married to the man he hate the most, the Count decided to replace her with Nullitas instead, as an act of revenge as well, since she wasn't of pure blood. Thus started the farce in which Nullitas had to live as her sister Maylene, with her life on the line.
Nulliitas: The Half-Blood Royalty