Shin High School DxD - Volume 2 Chapter 4

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

In the waves of steam and machinery, who could achieve extraordinary? In the fogs of history and darkness, who was whispering? I woke up from the realm of mysteries and opened my eyes to the world.

Firearms, cannons, battleships, airships, and difference machines. Potions, divination, curses, hanged-man, and sealed artifacts… The lights shone brightly, yet the secrets of the world were never far away. This was a legend of the “Fool”.

- Description from novelupdates

Is it wrong to face the perils of Dungeon alone, in a single-member guild blessed by a failed goddess? Maybe.

Is it wrong to dream of playing hero to hapless maidens in Dungeon? Maybe not. After one misguided adventure, Bell quickly discovers that anything can happen in the labyrinth-even chance encounters with beautiful women.

Only problem? He’s the one who winds up the damsel in distress!

“I'm one game away from reaching the master rank! I'll do it tomorrow, though. A true gamer knows when to refresh his mind and increase his victory chances!”Adam smiled in anticipation as he went to sleep on this special day.However, he could never have imagined the surreal awakening that awaited him.“What's wrong with my voice?!”“Claws? A tail and horns, too?”[Welcome to the demon realm. You have been selected to reincarnate as a Lord. Conquer this realm of fire and ashes, become its uncontested ruler... or die trying.]Reincarnated as an imp in the cruel demon realm, at the borders of the mythological demon Baal's territory, his life seemed doomed from the start.However, determination sparkled in his eyes as against all odds, he defiantly proclaimed.“No matter who decided to make me start as an imp, watch as I turn into a veritable devil. Even Baal won't hold a candle against me in the future!”Equipped with his unique talent, he started his lord's journey, ready to evolve and prove to those strange realms that demons were more than violent and deceptive creatures... at least he would try.