Elven girl, "Aria" is an adventurer. A small beast with an adorable face embraces Aria's fruitful chest, she decides to keep it as a pet and names it "Tama". At first sight it's just an average cat, but Aria has yet to notice that Tama is a former Knight and that his identity is not a cat, but a young monster of the strongest class "Behemoth".

“Sword & Magic Online,” a VRMMO consisting of 255 floors to clear, harbors a horrible secret: Everything from floor two onwards hasn’t been implemented yet. And all the devs ran away. Also, there is no magic in this world of swords and magic, the gold value has inflated indefinitely due to a dupe glitch, this kusoge (fixed term for a shitty game) is going down the toilet. And yet, there are friends enjoying this kind of game. For that reason and to avoid this world’s destruction (end of service), a youth named “Sasaraki” continues developing this kusoge world together with the mysterious girl Alice who dwells in the debugging room, and…? A VR kusoge development rom-com!