Responses
Maybe you mean Distorted Soul? :)
are you talking about this one?
https://www.mangago.me/read-manga/twisted_soul/
Your description kinda similar to this https://www.mangago.me/read-manga/stigmata_1/
the bottom had white long hair and the top was his guard (had black hair and black clothing) ??.??. i think. the bottom always wore white clothing and it was a historical bl. the bottom was pale and had green or blue eyes.