Max dreams of a harem and adventure and has a crazy superpower: he can fall asleep almost immediately. What do you mean it's no big deal? When he does that in the bookstore, he finds himself in the story he reads. And it's more than a dream, he can rewrite anything. He meets her favorite manga character as the staff of the Grande Library. Chasing after Princess Knight Aratsuki, he discovers the rules of his newfound power. He can dive into anything, and rewrite it forever, but only once. History books? Romance? Manga? Hentai? It's easy to find a way to exploit them all — but he has to bear the consequences.