The Black Hole
This is the coworker with a million had-to-be-there stories about their fantasy football league, last night's American Idol, or their cat. They treat conversations like suffocating headlocks, where the only escape is a dizzying collapse to the floor. And that's when they're sober.
Based God help you if you hear, "Did you ever see that episode of Friends where Joey..." and turn to see this tipsy wing bat locked on to you like a pursuing fighter jet. There's nothing you can do to shake 'em, your night's about to get shot down.