Hand Blumpkin
The act of jerking off while taking a crap.
“Chick left me, and all I’m left with are hand blumpkins.”
Hand-Carved Blumpkin
When you're taking a dump, and you start jerking off. Right as you're about to finish, you stand up and use your jizz to draw a face in your poop.
I just made a Hand-Carved Blumpkin, and boy are my arms tired.