"Ah, that," Dr. Velchiek replied, scratching his beard. "We honestly don't know. All of the adults have them. It seems to be some sort of ritualistic 'rite of passage' into adulthood kind of thing, but we're really not sure. We have cataloged a few of these, but there seems to be almost no correlation between the pony and the tattoo. Outside of the different types of pony, that is."