A girl I know was being fucked up the ass by a religious dude for over 2 years. The guy only wanted anal sex because he believed vaginal sex before marriage was sinful (hilarious), and he was petrified that his cock would slide into her pussy by accident, or that she would intentionally guide his cock into her pussy.
Now, you may consider that to be spectacularly stupid. But here's the kicker: the girl didn't include him as part of her number.
When I found that out about her, I dropped her immediately (I was fucking her for a little while). I can't date anyone that mentally retarded.