slow dancing in high school. In order to hide his level of fired up-ness, he used to push his posterior wayyy out so as to avoid any possible contact with the mid-section of the poor young lady he was dancing with. So much so that he cut a profile that made him look like he may have broken a hip or something.
Now, while he may have been successful in hiding his predicament from his dance partner, as you have likely gathered - it was no secret to the rest of the attendees at the dance what the situation was. Unfortunately for him, but hilariously for us, it became a running joke during the school year. And for the same reason that he never realized that people noticed at the dance, he never got the running joke either and just kept going to dances and breaking his hip the whole year.