Upon awakening as a demon lord in a new realm, Yuki is tasked with safeguarding a dungeon teeming with perils. Embracing his role in a world fraught with menacing creatures, he forges alliances and fortifies his stronghold. Despite facing formidable foes like a legendary dragon, a lovable slime companion, and a vampire maiden, Yuki's existence as a dungeon-dwelling demon lord proves unexpectedly serene. However, with a diverse group of companions and potential challenges looming, Yuki's tranquility is bound to be disrupted. Can he successfully embark on daring rescue missions, and will he and his eclectic family of monster girls navigate through a looming human threat? Follow Yuki as he navigates the complexities of daily life, his duties as a nascent demon lord, and the dynamics of his expanding monster girl and pet entourage.