Lai Rai Ken is a Japanese ramen restaurant in Seoul that serves tonkotsu ramen, mazesoba, and jiro ramen, located at the entrance of an alley near Seoul National University Station. The tonkotsu ramen uses a thick pork broth topped with chashu and seaweed, while the mazesoba is eaten by adding vinegar and rice. Customers pay in advance at a kiosk, enter in order of their waiting number, and must request gat kimchi and garlic separately. The noodles in the tonkotsu ramen do not match the broth in thickness.