A boy who dropped out of school inadvertently returned to the prehistoric era when the world was first opened. He personally experienced the glory and destruction of the ancient heaven, and witnessed the turmoil in the world with lich and thousands of races fighting in chaos. As a human race, how did he, who was born in modern civilization, survive step by step in that troubled world where lich and gods were fighting, and finally suppress the unrest and resolve immeasurable catastrophes.
(No system, no harem, humor, obscene development)
