A man walking down the street encounters a nun. The nun stops him and says:

“I am about to enter a missionary, but I do not want to become a true nun being a virgin, so I want you to make love to me, but there are a couple of conditions, you cannot be married, and you must do it in my butt so I do not get pregnant.”

The man is very perplexed, but decides to go with it. They go into an alley and have sex.

Directly after, the man, looking guilty says,
“I’m sorry, I have to confess to you, I am actually married.”

The nun looks at him concernedly and says,

“I am afraid I have something to confess too, I am actually a gay man going to a costume party.”