When a guy buys things for a girl or takes her to dinner & a movie, he's making an investment to get the pussy later. Made famous by Jerry lavigne jr.
Guy 1 : Yo, I gotta go make a pussy payment later. I gotta step it up, this bitch is high class. Taking her to Jamaica.
Guy 2 : The pussy better be worth it!
Every guy makes pussy payments, there's always a price. Might be a drink, or a vacation, all depending on the girl. Still a payment.