I’m not playing ‘Let’s Pretend’ just to make him stop acting like a 3 year old. No matter what sex you decide to call yourself (not that anybody cares in the first place, mind you) act like a civilized ADULT while in public.
That is not asking too much of anybody.
If he approaches the wrong cashier like that, he might end up in Urgent Care or worse.
This kind of thing is why in the past nobody really cared when someone killed them. Because we were all better off without them around, and they are better off dead than living out the nightmare existence of constant psychological self-torture.