Normally when you get someone pregnant it is a wonderful ordeal... weather it is a teenage mistake or not at some point there is happiness. The girl will hold her belly and and think for a moment "I am making a *new life" and smile, amazed at either her prowess or the divine miracle of conception.
From what I understand (I am not all knowing) the woman usually tries to get the father somehow involved in the ordeal. In recent years it is usually in the form of unpaid child support...
I'm not really going the blabber on about babies and pregnancy, but I will introduce a concept- The "vengeance baby."
I- hate someone... a lot. I can be civil to them, and polite, because I think it is the right thing to do in being polite. Mind you, I can be a polite asshole... but this lady that I hate... is also pretty attractive. So, the best way I can think of to just mess with them, is to take it to the ultimate level- The Vengeance Baby.
Operation Vengeance Baby has a simple goal, but to pull it off it would go through many steps...
1- Get her all hot for some guy. Simple enough, but finding an accomplice could be difficult...
2- Get her to agree to sex in a super dark room, bait and switch.
3- Get her pregnant.
4- Make her keep the baby.
5- Make her lose the paternity suit against the accomplice, it won't have his DNA so it's cool...
-Bonus points if it is a long and annoying trial.
6- Wait. Years from now, looking at her child she will see your face, and DESPAIR having raised the child of her mortal foe!
How much do you hate someone?