Its about winning. Its about the feeling of victory when you flood their womb full. They will bear your child. No other man will have claim to what you have earned by conquering her pussy, her very life. If its their first, you took her permanently from her future husband. If its her second or third and so on, you just conquered her family and proved shes just a whore for better men.
I love it when I get a girl into a bed and then she completely neglects to bring up pulling out after reluctantly agreeing to no condom. Like, they beg for the condom and ask for it repeatedly, but you slowly drag verbal consent for no condom out of them. Its like winning at convincing them to give themselves up, because they want to have sex with you so badly they'll risk what they are afraid of. Then, when the cards are all played, you sperm their pussy. Let me tell you from experience, even if they DO get mad, all you get is some complaints and that is the end of it.
For rules purposes, this post is fantasy. 😉