[mooning] wasn't enough to express my displeasure with king longshanks, so i decided to present him with the double hog back growler
dropping your pants and pushing the penis and scrotum between your legs before bending over and displaying your buttocks (and male parts) in a mooning gesture
"[mooning] wasn't enough to express my displeasure with king longshanks, so i decided to present him with the double hog back growler" What is the definition of "double hog back growler"?