The Ordinary-Yet-Extraordinary Dungeon Life of a Hero Returned from Another World.

The protagonist, Ichirou Hasegawa, was summoned to another world and, after a grueling ten-year journey of battles, defeated the Demon Lord. The moment he thought so, he was suddenly returned to his original world—modern Japan. Ichirou returned to the exact time and place he was summoned from. Furthermore, Ichirou himself had reverted to his pre-summoning appearance, save for his now muscular physique. However, in the Japan Ichirou returned to, dungeons inexplicably existed as if they were an everyday occurrence! Is this really Japan?

Please note: This story is a work of fiction. Actual laws and regulations may not necessarily apply within this work. Furthermore, all appearing characters, organizations, names, and countries are fictitious and bear no resemblance whatsoever to any real-world entities.

Also posted on Kakuyomu.