Summary Demon Instructor's Return from Kainu Manga
Demon Instructor's Return summary: The Central Plains fell to the invasion of the Demon Realm. A martial artist, Sa Bigang, was ultimately dragged into that infernal world. After surviving the brink of death and enduring hell itself, he awakens ten years before the invasion ever began. And now, Sa Bigang sets out to stop the Demon Realm’s return. To do that, he must restore order to the murim and build the ultimate force: the Undefeatable Corps. As the man who will rewrite the past and safeguard the future… This time, he will never lose