People in the Wasteland Accidentally Become Parasites

In the wasteland world after the cataclysm, the surface is unfit for survival, and humans live in underground bases. The time traveler Richard comes here. The host is a patient living in the base mental hospital, but he has a kind of awakening ability called a parasite, which can temporarily live in other people's bodies. Through parasitism, he discovered that the base was not the only human residence. There were still a large number of humans surviving on the surface world. There are not only ordinary people who are struggling to survive here, but also a large number of mutants and awakened ones, who possess magical and dangerous abilities. In order to get rid of the constraints of the base, Richard and his patients tried various tricks to escape from the base, but they were involved in the conflict between the surface and underground camps that had been hidden for many years.