Pandarus is Western literature's original creepy uncle. He acts as a go-between for Troilus and Cressida and is always reducing their relationship to nothing more than a steamy hook-up.
Did you notice how he kills all the romance between our lovebirds when he rushes them off to the bedroom? When Troilus and Cressida try to get all Romeo and Juliet on us (read: gush about how much they love each other), Pandarus asks "What? Blushing still? Have you not done talking yet?" (3.2.100-101). In other words, Pandarus thinks there should be less talk and more action, which is why he shoos them into a room that's furnished, quite simply, with a "bed" (3.2.211). (We talk more about this in "Themes: Love.")
At one point, Cressida even calls her uncle a "bawd" (a.k.a. a pimp), and by the end of the play, even Pandarus acknowledges that he's been acting like a "trader in the flesh" (5.10.45). FYI—Pandarus' character is responsible for the fact that, today, the word "panderer" is another name for a person who arranges sexual hook-ups. (He's also the reason politicians who play to our lowest instincts are said to "pander," so thanks, Pandarus. )
Of course, things don't exactly work out for Troilus and Cressida, so naturally, Pandarus is blamed for everything. In the final act, Troilus slaps him and says that he should scram because he's nothing better than a pimp or a servant: "Hence, broker, lackey!" (5.10.33).
But here's our question: why is Pandarus doing all this? Is he just trying to get his vicarious jollies, or does he have some deeper political scheme that just doesn't quite work out?