Pain Descends Upon New Eridu

[Slice of Life] [One Female Lead: Promia] I'm a new author, so please forgive me if some parts aren't well written. This is a Zenless Zone Zero fanfic with one female lead. The protagonist has a System and gains all of Pain's abilities after transmigrating into the game.

A sudden anomaly takes Yichen to a world he knows very well. With the power of a god, how will he change this world...?