YOW I HAVE A STORY IDEA. What is someone died and got reincarnated as a villain so she decided to change her faith and the heroin is a cold natural beauty. The twist is that the heroine will fall in love with the villainess and get jealous whenever she is with a guy she tries her best to make her fall in love. The 'male leads' think that the heroine like them and the villainess is jealous of her so they try to make the villainess' life living hell but the villainess thought that she deserved it so she just let it be . And when the heroine found out she turned the tables and punished the male leads. The reincarnated villainess soon fell inlove with the heroine.
Its up to you if you want it sad so, the sad part:
It was all too late. Because of the suffering that the reincarnated girl experienced, she became ill and she never said anything. She was dying.
Then the plot is up to you now