Responses
It kinda sounds like this but the FL has red hair in this one?
http://www.mangago.me/read-manga/this_girl_is_a_little_wild/
omg yes thank u, iwas mistaken
so i was reading thhis webtoon/manhwa a long ago, it was about this knight who was a girl but looked like a boy so she pretended to bf a boy in front of ladies and stuff and shhe had to face th demon king to save a cursed girl so her soul goes into the body of this girl and her original body dies. the girl is mistreated in her hhouse by her dad and step mom. her original body had blond hair and her new body had long black/dark blue hair