A man was driving down the highway, and sees a sign saying, "Sisters of Mercy, House of Prostitution, 10 miles"
Thinking it is some sort of joke, he pays no attention, until he sees a similar sign reading, "Sister's of Mercy, House of Prostitution, 5 miles."
Still unsure, he drives on, until spotting a third sign saying, "Sister's of Mercy, House of Prostitution, next exit". His curiosity getting the better of him, he takes the exit and parks his car outside the convent.
He knocks on the door, and tells the nun who answers, "I saw your signs on the highway, are they for real?"
The nun answers, "Yes" and tells him to give her $50 and follow her to a room.
He enters a room, and a second nun requests $50, and leads him to a door. Once he opens the door, he is quickly shoved outside by the nun.
He finds himself behind the convent, where he sees the final sign, "Thank you for you contributions, you have just been screwed by the Sisters of Mercy."