The act of a zombie forcibly removing its penis (easily done due to the rotting flesh), and then rapidly inserting the hole where the penis used to be
Zombie 1: “Arrrggh” *Wow I just had the best zombie wank ever!*
Zombie 2: “Argh” *Yeah thanks that was mine*
When put your hand in a bucket of ice for 15 minutes and have and wank
I got so bored the other day, that I got the ice bucket and had a zombie wank