This Wanted Criminal Comes from the End of the World

A wanted criminal who was originally in the doomsday world traveled to the planet Earth due to an "accident" during his escape and became a high school student. After contacting this world with Wang Yi's help, Li Xuan was pleasantly surprised to find that this was a perfect world without day and night acid rain, attacks by beasts, and the rule of chaebols. He no longer had to risk his life every day to hunt in order to survive. Just as Li Xuan was gradually adapting to the world, he discovered a strange thing. I have heard of the so-called ancient civilization buildings here in that apocalyptic world! "So, what you are saying is that I have to walk through the doomsday again?"