The heroine is a villain, and most villains will say "I will come back" like Big Big Wolf, or they will abandon darkness and turn to light under the influence of the protagonist, and then stab the protagonist at a critical moment. What is written here is the journey of the evil female villain to seek immortality and be reborn.
Reborn five hundred years ago, she became a love charm, seizing opportunities under the eyes of a female stallion. She was a devil, and she wanted eternal life.