People who are dying will enter a space called the mirror because of their longing for life. Jiang Nian actually entered the mirror because of a car accident. When he opened his eyes, he saw Liu Baisui lying next to him.
A little girl came over and said, "Want to live? I can help you~"
"Have you seen these mirrors? They are connected to various worlds. Some worlds are polluted because the energy of alien beasts and my energy are mixed. As long as you enter them and remove the pollutants, my energy can be restored and I can help you go back alive."
So, they signed a contract and after solving the problems caused by the alien beasts, they could return to their original world.
Intention: to be a good person