The sexual act of baking a pie for one's girlfriend, rubbing it on her breasts, and then licking it off. One then places the remainder of the pie in her vagina and has vaginal intercourse with her. Afterward, the girl gives the pie-covered penis a blowjob to remove the mess.
Person 1: What's that pie for? Are you having company over later?
Person 2: No, me and my girl are having some pie penetration when she comes over tonight.