The labyrinthine cafeteria Demon King's Cave suddenly appears in various towns.

The owner, a mysterious and beautiful girl named Chloe, the cook, a beautiful woman named Liu, a former adventurer with the nickname Demon Dragon, and the waitress, a cat-shaped demoness named Mya, run the diner, where they serve dishes made from high-class demon ingredients at a very reasonable price. Hearing this rumor, adventurers who killed the Demon King, legendary assassins, and other customers with one or two quirks become repeat customers...! In the cafeteria Demon King's Cave, which is connected to the labyrinth, crooked customers visit again today in search of delicious meals!