Two college students are in Ireland for a vacation when they feel nature calling. They stop at a rest area and are using the bathroom when a small man, no more than three feet tall, walks in.
He's wearing all green, even a little green hat with a shamrock on the brim. He walks up to the urinal and starts to pee. One of the college kids looks down and says, "That's the biggest dick I've ever seen! How did you get it that big?"
The little guy replies, "I'm a leprechaun, I can do anything."
The student says, "Can you make mine like that?"
The leprechaun smiles and says, "A favor for a favor?"
The student says, "I'll do anything."
The leprechaun says, "I want you to bend over so I can give it to you in the arse."
The student says "OK, I guess."
The leprechaun jumps up on a stool and does his thing. He finishes and asks, "How old are ye?"
The student replies, "21."
The wee man laughs and says, "You're 21 and you still believe in leprechauns?"