Yuzuki Nozomi is a young detective, calm on the outside but quietly chaotic within, his analytical mind always pulling apart the details others overlook. While proofreading the webnovel [The Hero That Left the Academy], Yuzuki suddenly finds himself thrown into its unfinished world, as a nameless extra named Ruvian castelor, who was obviously fated to vanish amidst the incoming calamity.

Armed with nothing but his will, Yuzuki discovers he can bend the very narrative, rewriting fates and strengthening those around him. But the manuscript he once proofed offers little guidance was left incomplete, its fate dangling toward disaster.

Now, in a world where doom is certain and knowledge is uncertain, he must fight not merely to endure but to change the inevitable. To survive, he will have to sharpen characters into allies, rewrite their weaknesses into strengths, and edit himself into more than just an expendable background piece.