WTF is a trap by the Encyclopedia Dramatica
A trap in short, is that which looks by the like it shouldn't have a cock but actually does. Traps come in two fruity flavors: Trannies, Fags, and fakes.
The Tranny flavor wishes it didn't have the cock and will surprise you with it, hoping you're too absorbed in their tits to notice the penis rearing it's head at your anus. If you're lucky, this means buttsex for you with minimal blowjobs! Some are even on hormones so when they speak they sound just like chicks. In this case, just close your eyes and pretend it's a girl.
The Fag version is a dude just out to get a free blowjob by pretending he's a she. No just closing your eyes and pretending here, as soon as this whore opens his mouth, the dream is gone. Remember: if balls are touching, it's gay!