publumpkin is like a blumpkin, receiving oral pleasure while excrementing, but only in a public restroom.
Mary Joe was asked by Billy Bob to give him a publumpkin, while stopped at the Flying J truck stop.
publumpkin: define #2
When you get a blowjob while you are on the john.
I was taking a shit when she came out of the shower…. and she gave me a publumpkin! WHAT A SICK FUCK!