Originally Posted by danielvutran
To my knowledge / understanding, most creepy guys are really just awkward lol. So the direct confrontation should scare them away and "wake them up" as to how uncomfortable they're really making you feel, and that'll be enough to get them to go away.
In my experience I've almost always found this to be the case. Someone who doesn't seem to get the hint that you want him to leave you alone, but doesn't set off "Danger Will Robinson!" alarm bells in your head is usually just socially awkward. I can completely relate to not wanting to hurt people's feelings, especially when you can tell that they aren't purposely being aggressive or creepy.
That's why everyone else's advice to just be direct is so true. If hints haven't been working, don't keep trying to drop hints. Move on to the direct approach - "I'm sorry, but I really just want to hang out with my friend at this convention. I would really like it if you would stop following me around, please." If he asks why she can say it's because she has a boyfriend and he's making her feel uncomfortable. That should be enough answer for anyone.