Most Helpful Guy
This is called the clawing attitude, happens with guys who become desperate or have the illusions that they're scoring with you. Unfortunately, these guys ride high on these emotions. I'm pretty sure he won't handle any sort of rejection in a proper manner. So if he's in close vicinity to you. Back off, slowly. If he isn't, tell him. It isn't working. No need to be courteous. That'll only boost belief that its working. Sadly, the irony is the nicer you try to be the harder they try.