You need to be up front and brutal quickly, almost as soon as he begins talking to you. You may even have to interrupt him. He needs to know you are in control and he has no say. You can still be "professional" about it, but you can't be sweet and you need to be quick, before he has any investment in you. Yes you may "offend" some of the more sensitive guys, but many will simply appreciate the honesty even if they may not have liked the delivery. Remember, a guy only has so much time in a night to find someone, so the more you can save their time the better for them. The only ones left are the ones who are think they are entitled to be inside every woman on Earth, and her consent is a secondary matter, if even that, and then the guys who will regard a negative response as an affront to his masculinity and thus he must try to reclaim his dominance/masculinity. There's a fair amount of overlap between the two groups too. I suppose there are a few guys who are otherwise nice guys who are clueless but, frankly they lack the social skills to such an extent that they are rare sights at social events anyway (hence why they don't have the skills in the first place). Never, EVER assume that this last type of guy is the guy in front of you if you have turned a guy down and he won't take the hint. Some of you will want to think the best, but you are putting yourself at risk and even the "nice guy" needs to have his behavior corrected, ruthlessly, if necessary (he his clueless after all). Assume the guy intends to do you harm, physically or emotionally because there's a good chance he does. Escalation is warranted and leave no doubt in his mind but not necessarily extremely confrontational, yet. Something like, "That, apparently didn't work so let me spell it out for you. Go away." If he continues, then he has become a threat and act accordingly. You can leave, but ask for an escort and have you hand on a can of defensive spray, just in case. This is NOT a case where you want to avoid being a bother. If there is a host inform them, and if they don't remove them, you need to remove yourself, again with an escort (never alone, NEVER). If you can't find an escort, find a new crowd to hang with and call a cab/Uber/ect. and stay with the crowd until arrival. From a selfish standpoint, back when I was young and courting, I loved an opportunity to provide an escort even if I was hitting it up with a woman. It would prove to the person I was talking to that I put others before myself and I generally care about a woman's safety, even one I don't or barely know. If I do that, I can potentially show two different women that I am a decent prospective lover. And generally, those are the signals you want to be sending to women, guys.
