At the age of 10, Tooru died—then was naturally reborn in another world as a baby.

With full awareness of his past life, he grew up to become a fighter, an adventurer, and eventually, a Holy Hero chosen to defeat the Demon King. He succeeded... but died again at age 20.

Strangely, all of that only lasted one second in his original world. He returned to his old body, as if nothing had ever happened.

Seven years later, now 17, Tooru lives a normal life as a lazy high school student, an insomniac who hides a past no one would ever believe. But when a mysterious light appears in his classroom and teleports every student to a strange world—Tooru realizes one thing:

Maybe the story of a man who reincarnated has already ended,
But this time, it’s the story of a man caught in a far more complicated otherworldly life... once again.