Am i a bad person...
That's a terrible situation! Look, that is not a situation in which you should do anything related to sex. The situation is that she is in prostitution. Some girls may like it, though others may not. You know what emotion your girl was experiencing while she told you. If she was crying - or blue, never do the task. If she was turned on by it, depending if she " REALLY ", and I focus on "really" for a purpose, liked it, then it's okay. Though, it seems that she did not. She's most likely in a fragile state, and needs an ear to talk to. Just apologise, remind her she's a great person, and never do so of the actions that were discussed: have her have sex for money, and never have sex with her so forcefully, or rape-like.
that doesn't make you a bad person. and you're not even in a relationship; you're just fucking a slut, so fuck her.