When you grab a 2 liter of mountain dew, put in your fat girlfriends asshole and empty it in there. Then you tongue punch her fart box and drink the dew out the booty hole.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.