When one, or many, ejaculate into somebody's apple juice prior to them drinking it by fapping. Usually performed by men, but on rare occasions by stealthy women.
Jackson hung above the school cafeteria in the nude for hours upside down, waiting for the perfect moment to engage in the craft and art of "Fapple Juice."
It's the 2nd pie in the famous two for $1 deal at Mickey D's. After you've finished your entree and your 1st pie for dessert, open the box of the remaining pie and insert your penis. While securing the closed end of the pie box with your index and middle fingers, fuck the pie.
Elliot: "Let me have a number 3 with a coke and a couple of fapple pies...HOT!" Cashier: "You're going to fuck both of them?? My god you're a savage!! Elliot: "One for the ride home bitch."