There are demon catching yamen in the world, killing demon beasts, taking demon pills, increasing one's cultivation and reputation, but little do they know that they have become a sinner in the demon world.
Humans and beasts are both living beings, and they are symbiotic. However, humans cannot see the spirituality of beasts, and only kill for pleasure.
Fang Lin traveled through time and became a demon king. He set up a yamen in the demon world to deal with the sins of the human race. He rehabilitated the demon world and set a good path for himself.
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Yin and Yang have two sides, good and evil. I learned the demon way and the immortal method from a piece of fairy jade. I am a demon and a saint.
If you are a fairy, I am a devil.
If you are a devil, I am a fairy.
Fairy or devil, my sword has the final say...