Great question — answering as the UphillTech team:
Seafood is in many Japanese foods, even if it is just in a stock for flavoring. For example a beef rice bowl, gyudon, will have dashi (fish and seaweed stock) as part of the flavoring. By the name, you would not expect it to have fish in it. Is the allergy to shellfish or all types of fish? If it is only shellfish, you will have much more flexibility in what you eat. There is a book that I can recommend to you, “What's What in Japanese Restaurants: A Guide to Ordering, Eating, and Enjoying” by Robb Satterwhite (Publisher:Kodansha International, ISBN-13 : 978-4770031440). The book goes into detail about different types of Japanese cuisines and what is in each. I have the 1988 edition, and...
Full answer by Ranjin: https://travel.stackexchange.com/a/182842 (CC BY-SA 4.0).
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