Sex under false pretenses
This happened about five years ago, but everything turned out ok in the end. I was recently divorced and had moved about 50 miles away -- close enough to visit my kid, but not so close that I'd run into the ex. I met a woman in the new town, and we started dating. Her biological clock was ticking and she wanted a baby, and preferably a husband too, but a baby above all. I told her I wasn't anywhere near ready to marry again and might never be. She said that was ok, but she wanted a kid and she had plenty of money, and didn't want any support. I didn't say no, and since we enjoyed each other's company, we became a couple and just let nature take its course.
The thing is, I couldn't have gotten her pregnant. I'd had a vasectomy after my son was born. I was just wanting the sex. I let her track her cycle, use fertility montors, take home pregnancy tests, all the while knowing she'd never get pregnant, at least not by me. This went on for the better part of a year, when she said that maybe I ought to be tested because she knew she was fertile. I said I didn't think it was meant to be for us. We broke up shortly afterward. About a year and a half later I saw her in a restaurant with a man and she was very pregnant, so she got what she was after.
Your just the worst type of terrible prick I could ever think of, I wish they cut your cock off instead of your nuts just being changed they should have gone too