Takuma Sakamoto, a reclusive gamer, wakes in another world wearing the body of his overpowered avatar, the Demon Lord Diablo. The two girls who tried to summon and enslave him, the pantherian Rem Galleu and the elf Shera L. Greenwood, watch the spell rebound onto themselves, which leaves them bound to a demon lord far too socially awkward to say so out loud. This third season continues their travels.