Waking up from Another Person in Another World

An ordinary high school student traveled through time into the body of a boy from another world, and had to live as a boy in an unknown world. He used his own soul to survive by borrowing other people's identities. By chance, he, who was originally a high school student, discovered that there was a bigger secret hidden behind the boy... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.