This is kinda vulgar but who cares, it reminds me of good times.
So this guy finds this small dude in the forest and the small dude says 'Guess what I'm a leperachaun!" The first guy says "No your not!" and the small guy says "Yea I am. I even have a pot of gold." And the first guy says "Really? Can I have some of it?" The small guy says 'ok but only if you let me fuck you in the ass.'"
"You gotta be kidding me."
"Either that or no deal."
The other guy says "fine" so they take off their pants and they start fuckin, and as they fuck, the bigger guy says "I can't believe I'm doing this" and the smaller guy says "I can't believe you think I'm a leperachaun!!"