No only Triangular
Onigiri is the soul food of Japan, rice is the most important food for Japanese. Shaping rice into a different shape with seasonings and seaweed, making it convenient to eat using hands in different circumstances. In Japanese anime and drama, the onigiri is always triangular, actually, they are in different shapes depend in regions,
In the Tohoku region, the onigiri is in tambourine. In Kanto and Kansei regions, the onigiris are triangular and cylindrical respectively. While the onigiri is spherical in the Chubu region. Many Japanese do not know about the different forms of onigiri in Japan!
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