One day, Kazuya Torino is visited at his apartment by the goddess Luna, who asks him to manage a dungeon in another world.

Reluctantly becoming a Dungeon Master, Kazuya first decides to train the goblins and slimes.

Two days later, a party consisting of a swordsman, a mage, and a former princess-turned-sl*ve infiltrates the dungeon. Kazuya and his goblins meet them head-on.

From building open-air baths to educating newcomers, the Dungeon Master’s days are as busy as ever!