The story is that the mc's brother will be a tyrant and she got back in the past and now she wants her brother to not be a tyrant. They both have black hair TTIm so sorry for the vague description, I tried to remember it as much as possible
This one? https://www.mangago.me/read-manga/second_life_of_a_trash_princess/
YESSSS DAMN HOW DID U EVEN
The story is that the mc's brother will be a tyrant and she got back in the past and now she wants her brother to not be a tyrant. They both have black hair TT
Im so sorry for the vague description, I tried to remember it as much as possible