In her pussy.

Risks be damned, you're cumming in her pussy tonight! As you plunge into her again and again, she starts to notice you tensing up. You can see in her eyes the exact moment that she realizes what you're about to do. She starts shaking her head back and forth, trying to slip out from behind your hand. She's crying, screaming, but only you can hear her.

Finally, your cock has had enough and unloads. You fill her uterus up with cum. You know it and she knows it. You roll off of her. She looks over at you with hatred on her face. But she knows she can never turn on the father of her child.