P1: What's the difference between a kid and a hooker?
P2: I don't know.
P1: Wow, you sick fuck!
P1: What's the difference between a kid and a hooker?
P2: I don't know.
P1: Wow, you sick fuck!
Alright, listen up, smoothbrain. This "joke" is banking on you thinking of something nasty when asked the difference between a kid and a prostitute. The punchline is that you're a sicko if you don't know the difference (because you should not be thinking of such things). And judging by your lack of critical thinking, you probably are. Facts.