[QUOTE=Cintixtreme;3392262]If they have mutual friends, his profile could have popped up on her page as "People you may know". Facebook does that with friends of friends. So she may have simply seen the picture from that and recognized him. Ain't the internet great?[/QUOTE]Facebook links with your contacts. If you have a hookers number in your phone book and their number is linked to their FB account, at some point, FB will suggest them as a friend. Works the same for the hooker. If she has your number in her address book and you use your real number (the same number you have linked to your Facebook account) for your hobby activities, her FB will eventually suggest you as a friend for her.
If you access the recommended friends list on your cell phone, it would be very easy to accidentally hit the send friend invite. I've done it before. If your realize that you invited someone by accident, you can quickly undo it. If you don't realize it, and keep scrolling, the invite is out there.
If you get an invite from some chick you payed to fuck, I'd say decline and move on. Odds are it was an accidental invitation. Perhaps she didn't even remember you as a paying customer. Maybe she saw you on the common friend's friends list and was like this guy is hot. Look if these girls had as many sticking out of them as they have had stuck in them they'd look like a porcupine. I can't imagine they remember every face that fucks them. He'll accept the invite and try to get some free pussy out of the deal.
Even though I use a texting ap for my activities, any saved hooker phone numbers and names are still in my address book. I have found many girls on my suggested friends list.
As far as common friends go, I've seen quite a few girls that I've had common friends with. I don't believe it is that uncommon to have a friend or to in common.