Hei Shizai just became a cadre, and was accidentally selected by Shu's consciousness during a mission and sent to another world. Shu's consciousness asked Hei Shizai to help him in exchange for granting him a wish. The main purpose was to promote the world process of the other world and achieve a Good Ending, thereby obtaining the consciousness energy of the other world to restore Shu's consciousness energy.
The main different worlds are Mingke and Curse. In the different worlds, Zai's identity and age are also different. There is no official CP, you can eat it at will.
Purpose: To be happy