when you place flans on a person's back and wank onto them until you cum and then they have to eat them
Matthew pulled a Jack back flan on me last night
He's basically David Guetta in a nickname
Dude: Do you listen to Jack Back
Another Dude: Who the fekfkekkf is that?
Dude: Bro it's David Guetta!
Another Dude: OOOOOOOOOOHHHHHHH!!!
To pleasure onses self to old pictures of celebrities/porn stars who are currently past there prime.
"She may be ugly now, but I keep some of her old pictures from the 90s for a throw back jack"