Well, usually when someone wants to say "excuse me" after bumping into you...you can tell he/she said something like that. That's all I would expect if some dude were to accidentally bump into me.
However, if he wished to continue to "dance on my ass" since it's so damn packed in there, permission is still a good idea unless you want a heel ground into your toes or a strategically placed elbow.
Okay, but you do realize that no one goes up to a girl in a place like that and goes "Hey, I was wondering...uuh....I was just thinking...uhh..can I uhh....can I uh.... dance on your ass?" That's why I mention eye contact. Everything is subtext from my experiences. You say "excuse me" to the girl, then maybe you brush your arm against hers or something, very slightly. She turns if she's interested, or she just doesn't look at you if she's not. If she is, you both look at each other. Then usually the guy is supposed to do something like gently pull her by the arm towards him or twirl her into him or something like that. Then it's either a "hey" or a "what's goin on?" and you're both off, freakin to it.
At least this is the courting gestures I have witnessed.
And that's funny, I never witnessed a heel to the foot or anything. You ever really do that? Must be some real Cassanovas out there. :)
