When you shotgun a beer, only casually. It should require a minimum of 3 separate drinks/pulls and you must hold the can side-ways in a casual manner. A casual shotgun portrays both class and sophistication.
Someone lights the nug, as you squeeze-in to suck the weed smoke into your bunghole.
Then the other person proceeds to put their mouth on your ass while you squeeze out(fart) the smoke into their mouth as they inhale.
“Hey, you two girls should totally dirty shotgun eachother, it’d be super hot!”
“One time I tried to dirty shotgun my bf, but he kind of sharted during, so I never did it again.”
Referring to the act of fellatio (or autofellatio) where the receiver gargles at the exact moment of climax, whereby the semen sprays out of their nostrils.