What is Upper Decker Double Blumpkin?
1.
The act of sitting on the top part of a toilet and shitting while getting head by the girl who is strattling towards you on the bottom seat while also taking a dump at the same time.
The raunchiest act of the famous "blumpkin" to the next extreme calling it the Upper Decker Double Blumpkin.
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Random Words:
1. 
When a person who is playing a video game who is a noob, or sucks very badly at it, leaves to get food or drinks while still in the game..