【Book version receiving rave reviews, now available from Kadokawa Sneaker Bunko!】

【Manga adaptation now serialized in Dengeki Daioh!】

"—This dungeon is unacceptable!"

One day, Nalgoa, a mere monster, is appointed as the mid-boss of "Shijima's Cave," the first dungeon closest to the heroes' headquarters.

There, he finds nothing but unmotivated employees (monsters). Convinced this situation wouldn't do, Nalgoa embarked on a major reform of the dungeon. His efforts paid off, and within a year of his appointment, Shijima's Cave transformed into a grand labyrinth capable of repelling even seasoned hero parties!

However, those who arrived were legendary heroes who had already defeated the Demon Lord. To protect his beloved employees, Nalgoa single-handedly challenged the heroes and was defeated, and then—for some reason—he is reincarnated into a world 100 years in the future!

An exhilarating mid-boss fantasy unfolds in a world 100 years later, alongside the employees of Shijima's Cave, which has become a legendary grand labyrinth! It all begins here!

※Chapter 2 has concluded!