A Petracon is a person who lacks coordination, a sense of style, and is often times very geeky, nerdy, and/or dorky. Hiking your pants above your waist, calling shoes sneakers, wearing a Fannie pack, and being socially awkward are just a few of the many characteristics of your neighborhood Petracon. Odds are, most petracons aren't aware, or simply don't care that they are this way.
Look at that petracon walking like a dinosaur and looking like Napoleon Dynamite. I doubt he's ever been laid.