Sorry, how are gay couples treated in Japan? People are conservative here, so no marriage, but from all gay couples I know here, they’re doing fine. Now, you can talk about PDA, but that kinda includes the straight couples as well to a point.
Edit: Just as a side note, I saw western people bend over backwards to please people when I went to Japan. It becomes a self-fulfilling prophecy some treatment they get will be positive when you behave in such a way (like a guy bowing 5 times just for getting his photo taken, stuff that would never happen to anyone else) almost embarrassing really.