Normally I hate it when anyone calls me Johnny, but a guy I knew in college decided I should be "Johnny Koalas". We were hanging in the student lounge with a bunch of the other dorm rats and I was wearing a tank top that had made sort of pressure-mark "scars" on my back. I walked over to a vending machine and this guy Mike says, "Damn, what made those gouges on your back?" Wolf whistles indicated what the gutter-brained onlookers were thinking, but I said, "Nah, it was a drop bear that got me when I was a kid." My down-under roots were a common topic of discussion, and the natives were suitably horrified by my explanation. Later the Mafia nickname thing came up in regards to watching Johnny Dangerously.
Years later someone asked me if I had gotten surgery to remove the scars. I guess the pressure marks from the tank top had really been livid. Weirdly, I knew exactly what she was referring to and was sort of incredulous that to some degree she had believed my carnivorous koala story.