This is one of the small appetizer or like a cover charge. So you have to pay even if you have not orderd this small appetizer or you don't want to eat it.
If you go to a type of Japanese restaurant such as Sushi restaurant, Izakaya(a type of Japanese pub restaurant), or traditional Japanese restaurant, you will see this food.
Sometimes you will see in the menu, sometimes you will see without the ordering. Normally, it's around yen 300 to yen 1,000.
Sometimes it's an artistic and very tasty food especially if you go to a good restaurant.
If you see this word in the menu, let's try. Normally, the volume is small but you will know the quality, manner, sense, etc of this restaurant.
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