You are reborn as a vicious extra in a popular romance-fantasy novel.
In the original story, this character is a beautiful but spoiled noblewoman who bullies the heroine, provokes powerful men, and eventually becomes an obstacle to the romance between the heroine and the male leads. She is not the main villain. She is not even important enough to have a proper ending. She is simply the girl everyone loves to hate. Until you wake up in her body. And realize that the original body is destined to die.