The Secret of the Goblin Cafeteria

The Goblin Canteen has been a secret place and transit station for goblins for thousands of years. Goblins who want to come to human territory must go through approval and review, so there are not many guests. Humans can't see or come in, but the heroine's grandfather's grandfather I entered this place by chance and ate the food of the goblin. I was forced by the idle male protagonist to write a contract. He had to run this goblin canteen for generations, and he had to be the store manager and chef. My grandfather's grandfather was so confused that he sold many generations of people.