Her life had already been sentenced to death by a terminal illness, and only the cold countdown was left ticking in her chest. On her deathbed, she touched the strange opportunity in severe pain - at the cost of her soul, she became a demon, but she was also involved in a never-ending cycle.
Every time she signs a blood contract, she has to use the other person's life as fuel in exchange for everything the other person desires. The tearing of underworld and hell caused the order to collapse, and the wandering demons caused countless tragedies in the world. Her blood contract was one of the contaminated rules, and she eradicated the hidden evil seeds step by step.
When she finally broke out of the cycle, she discovered that the so-called "salvation of the world" was actually her own redemption...
World view: The underworld merges with hell, tearing apart the space. Most demons pour into the human world and become demon dwellers (half-human, half-demon, with human consciousness as the main body, and their bodies change). However, a few demons are still scattered in the world to do evil. The purpose of the existence of demon dwellers is to get rid of the evil demons who wander around and kill all evil people.
Intention: None