Ryousuke, an aspiring light novel writer who posted novels on a free posting site on the internet finally gets his novel, 「Yuusha Tensei 」, turned into a light novel, but on volume one’s day of release, he meets with an accident. When he comes to, he finds himself in the world of the light novel he wrote,「Yuusha Tensei」. He has reincarnated as the hero’s greatest rival and the popular villain, Carlo-De-Medici. This is five years before the hero will be reincarnated. Ryousuke resolves himself to play the villain perfectly as Carlo, and lead the yet unfinished story of his creation to its ending――