Isekai kara Kita Mazoku, Hiroimashita. - Ukkari Moratta Maryoku de, Dungeon no Aru Gurashi o Mankitsu shimasu.

Keita Todo, a company employee in his twenties, has become unemployed after quitting his job because he can no longer stand the absurdity of being a company employee. While leading a lazy life, he happened to meet a little demon and a fluffy dog, on his way to the store. In order to return to the world they came from, the two decide to conquer a "dungeon" inhabited by various resources and demons together.

The dungeon exploration life of a man in his twenties, who has escaped from the bonds of society, begins.