Do not shit your pants in public with your RL friends, especially not in a cinema.
That is a poor idea. You will regret it I am sure.
Its pretty risky being padded around people who don’t know, as it is! without adding that particular complication.
It is also an unreasonable thing to do in a public space. Don’t do dumb stuff and give the whole community a bad (worse) name.
Not the supportive advice you wanted maybe, but I recommend you listen to it. Enjoy your kink, enjoy your friends, don’t screw both things up for yourself.
Good luck