Maou-sama, Retry!

Akira Oono is a regular working person who takes care of the MMORPG Infinity Game. After 15 years of running it, Oono decides to turn it off. But at midnight, he finds himself in the body of Hakuto Kunai, the Demon Lord of the game!

Hakuto then sees a monster chasing a little girl called Aku. He gets rid of the beast easily, but he's still not sure what's going on. He doesn't remember making the girl or the monster. To figure out what's happening, Hakuto takes Aku with him and starts an adventure. He wants to find out who brought him to this world, even if it means causing some trouble along the way.