B is for bathroom, basement, and boyfriend.
"Excuse me, do you work here?"
"Yes, how can I help you?"
"What beautiful eyes!"
"Thank you...how can I help you?"
"Excuse me, the man in the bathroom is taking so long. Maybe he is asleep. Is there another bathroom in the library?"
"Yes, down in the basement. If you go out that way and down the stairs or the elevator, it will be right in front of you when you come out."
"Oh, thank you! What button do I push?"
"B, for basement."
"Do you have a boyfriend?"
"Oh. Oh wow...What button do I push again?"
"B, B for basement."
(Picture from http://www.textalibrarian.com/mobileref/42-library-related-memes/)