My fiancé who has a severe Gluten allergy loves this place! We go very often and recommend it!
The host was very friendly and very knowledgeable about gluten free as he couldn't eat it either. They had braggs and tamari sauce for gf soy sauce replacements. He recommended the mussels without the sauce and I got two rolls. The food was good but I got horribly sick afterward. I think its possible the kitchen made the mussels with sauce...but I have no idea. It really surprised me 'cause I don't know where it came from. Just be careful.
Osaka is gluten free friendly! Ask your server!