sperm-off
When two guys engage in double vaginal with the goal of knocking up the girl. Winner is the guy that winds up knocking her up with the loser having to suck him off.
Jessica: I'm still a little sore from that sperm-off last night
Kate: Which guy do you think will win?
Jessica: Well I would love to have Steve's baby in me, but it would also be so hot to watch him suck off Mike.
Kate: Which guy do you think will win?
Jessica: Well I would love to have Steve's baby in me, but it would also be so hot to watch him suck off Mike.