I only found out that my girlfriend used to be a bar girl after I was dating her for about six months. I really would never have guessed, because she doesn't speak a word of English, she's extremely shy, and she's not particularly great in the sack either. But the story came out later...
It was a big shock to me because I've always had a rule that I won't date bar girls. But hey, it's a rare case where I didn't know that before, and her story was convincing enough that I have given her the benefit of the doubt. Apparently, she was bullied into it by her narcissistic, drug-addicted mother who constantly demands money from her and puts her under a lot of pressure to do it. She lasted about two months, absolutely hated it, and had 2-3 very bad experiences, judging by what she told me.
Not surprisingly, she doesn't like talking about it at all, but fortunately she seems to have moved past it.