Depends on the situation and why you around certain people to begin with
Nah, still doesn't give breh a pass. She could've gone over there to flirt, and maybe even expected him to maybe get a bit handsy, but women really aren't expecting you to bust their titty out out of nowhere, especially if the conversation hadn't progressed to that level of physicality. And even then, if she was cool with popping it out for him, it doesn't mean she was good with him pulling it out for everybody else to see. Private titty can't always be public titty.
Either way, brehs can't be out here moving like they're still in sophomore year of college or something. If y'all both grown, you might as well assume the woman isn't cool with you snatching a breast out unless you're in private, and she was clearly giving you the green light.