Went to the tokyo location and the osaka location, the curries can vary a bit by region and by day. They have very informative lists of allergens if you ask, and even if some curries don't have the GF yellow designation, some are still gluten free. The curries and soups are very tasty and it's a good quick place to get some food when traveling (they tend to be near stations).
— Somewhat
— Gluten-free items are marked on the main menu
— Some
— Good