Role reversal, but when I was about 23, I took a pizza delivery and some cute brunette forgot to bring half the order up the stairs to my apartment. I went down to get it with her so she wouldn't have to make a second trip. I paid and tipped at the car, she got really nervous and said something about how she felt so bad and wished she knew how cool I'd be about it, then stood there, expectantly, playing with her hair and giggling.
I was just plain hungry, and completely missed the real-life porn scenario unfolding in front of me until I had already gone back upstairs. Literally this: