This one could go a few different ways. I could help a prostitute escape, but her pimp finds me before I could make my own getaway,and to punish me, he makes me take her place. Or a street gang could see me and decide that I could be a good earner for them, after some..training.
Or it could be the prostitute herself that does this to me after I meet her and buy her a coffee. She swaps clothes with me and leaves, leaving me to be found and to be made to take her place.
If this interests anyone, let me know.