My girlfriend got into financial difficulties and accepted a loan from a shady local business man. It was all unofficial and the terms were unreasonable, but she needed the money desperately so accepted. As expected it wasn't long before she found herself unable to pay off the instalments and received a visit from the man and two of his associates.
They told her that each week she couldn't pay them, they would either take away items of her property to sell against the loan, or she could pay them with sexual favours. Feeling that she had no choice, she opted to have sex with them. This went on for weeks and even when I was there, they took her upstairs and I had to sit and listen to them fucking her. I used to make her describe in detail everything they had made her do.
I have to confess that the whole situation made me as horny as hell and I often had her stay on the bed exactly as they had left her, so that I could relive the experience as she described what they had done. It was so exciting to take her myself while she still had their cum oozing out of her.