I was going to leave a cheeky comment here, but looking at what other dudes have said (predictably) I've decided to be serious. Asking a question like this is always fraught with peril because most guys would reply "I would LOVE it if someone sexually harassed me!"

In order to make it relatable to them, I suggest asking them if they'd be comfortable with a large man coming up to them, twisting their nipples, commenting on their ass, and letting them know how much they'd like to tap it. That'll shut em up!