Seafood Buffet Dining Ginza Happo is a seafood buffet in the basement of Don Quijote Ginza that serves king crab, snow crab and wagyu without limit. The crab comes already cooked and is grilled briefly before eating, and sake, beer, soju and soft drinks are also unlimited. It opens at 4 p.m. and has a two-hour limit, so visits are by reservation. The sushi and fried items are plainer than expected.