When you fantasize while masturbating then someone appears in your fantasy unintentionally, in most cases someone who should not be there.
"I was cleaning the rifle then all the sudden out of nowhere your wife makes a pop in" "A pop-in? What the fuck? Get her out of there " "I tried she wouldn't leave , it wasn't my intention i can't control who pops-in"
by Johnny Martinez March 01, 2005