n. adj. A greasy piston is a person that indulges in activity of the homosexual persuasion. Greasy coming from the chocolatey brown color of shit, and piston from the penis and it's motion in and out of another man's rectum.
I think you are a greasy piston.
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
Buy the mug