One of the best things about bars is also one of the worst: you never know who you're going to meet. For every Cute Girl Who Seems to Legitimately Laugh at All Your Jokes (who may or may not be the grown-up equivalent of the Summer camp gf from Canada), there are plenty of people the bar could do without: the ones who ruin everything from the simple ordering of a drink, to your entire night.
So you should peruse this comprehensive list of every watering hole's worst inhabitants, realize you know every single one of them already, then make sure you're not The Lurker.
The Guy Looking For a Fight
Yes, I did bump into you. I'm sorry, but there are 300 people jockeying for space. No, I don’t want to take this outside, I just genuinely think that Affliction shirt is stylish.