Can your dietary requirements be accommodated in Japan?
Being vegan or vegetarian is not very common in Japan, especially in small towns. Tofu is plentiful but many tofu and veggie dishes may contain fish.
Maintaining a fish free diet will be a challenge. You may find yourself eating a lot of rice and seaweed (also delicious). But you may want to be prepared to stop at convenience stores to stock up on protein bars and nuts. We will do our best to accommodate dietary preferences and restrictions but some small hotels are not able to adjust meals.
If you are willing and able to eat sustainably sourced fish it will be easier.
A gluten free diet can be accommodated though may be a bit bland if soy sauce is a concern.