The act where the woman is taking a shit on the edge of the toilet while the man, or another woman, is eating her out. An easier, but messier variation is where the woman shits on the man while he eats her out.

This is not to be confused with a Blumpkin, or a Reverse Blumpkin, which are two different, but closely related things.
The woman was tired of giving her husband blumpkins all the time, so she forced him into a Double Reverse Blumpkin.
by KinkyMaster September 13, 2017
Get the Double Reverse Blumpkin mug.
When someone is doing an upper decker and the person on the lower decker is is giving head and takeing a shit at the same time.
I walked into two people doing a Double Decker Blumpkin in your bathroom.
by sick mo'fo December 7, 2012
Get the Double Decker Blumpkin mug.
Takes two people, one takes a dump in the tank of a toilet while the other faces backward on the normal toilet seat dumping while giving the tank dumper head.
Yo, eff those tool bags, they wouldn't give us any beer so Crystal and I pulled a double decker blumpkin in their master bathroom and rolled out! Try flushin that bitches!
by Vern1234 March 10, 2010
Get the Double decker blumpkin mug.
A double donkey blumpkin is a sexual act wherein two men sit on toilets facing each other, and recieve fellatio as they evacuate their bowls. Both men should climax simultaneously, and at the moment of climax punch their partner in the occipital lobe as hard as possible.
Rex, Jan, Jill and I had a Double Donkey Blumpkin party last night... it was a mess, there's shit everywhere.
by Dr. Hotte Karl June 21, 2010
Get the Double Donkey Blumpkin mug.
The act of, in this very exact particular order: finding a sexual partner and take them to eat a substantial amount of Taco Bell with you. When you both inevitably need to take a diarrhea shit, do it at the same time, with the submissive sitting on the bowl and the dominant sitting on the opened top tank. During the shit, the submissive will perform oral sex on the dominant. When the dominant finishes on the submissive’s face, they must punch the submissive in the nose to create a mixed fluid of blood and ejaculate on their face. Once both parties complete their shit. They will perform a reverse sixty nine on each other until both anuses are clean. Then the dominant must lick the submissive’s face clean.
Man 1: hey bro, why did you break up with your girlfriend? She seemed really nice.
Man 2: nah bro, she was so selfish, she wouldn’t even do a kentucky jelly doighnut upper decker double blumpkin supreme with me!
Man 1: oh man, I didn’t know that, what a selfish bitch!
by Dr. Heinz Doof August 30, 2021
Get the kentucky jelly doighnut upper decker double blumpkin supreme mug.
It's the act of the man taking a dump in the tank of the toilet while the woman takes a dump in the bowl while giving the man a blowjob while a third party performs a golden shower.
Dude, last night Stacey and Dave and I did the upper decker double deluxe Blumpkin, it was gnarly!
by Reedski March 22, 2015
Get the upper decker double deluxe blumpkin mug.
When a man extracts his fat monkey turd and shuvs it up the woman's pussy while she is giving him head. Difficult to do.
It started out as a normal blumpkin, but then I turned it double duo.
by Turkmanistan May 8, 2003
Get the Blumpkin Double Duo mug.