After Being Polluted by the Back Room, I Was Surrounded by Fake People and Became a King

In the near future world, human civilization and supernatural beings are in a delicate balance, and border checkpoints are the first line of defense for mankind. "The most terrifying thing in the world is not monsters, but 'them' in human skin." ——Border Checkpoint No. 49·Survival Manual Article 1 Monsters from the "back room" can perfectly imitate humans, blend into society, reproduce, replace, and eventually devour civilization.