The mystery of my pants

In the interest of fairness I should probably point out right at the beginning I have no clear proof a Rosemount-area skateboarder is responsible for what happened to my pants.
Here's what I know for certain: when I put this particular pair of pants on last Wednesday morning they were, so far as I noticed, free of any major blemishes. I also know that not long after I left a day camp held at Rosemount's skateboard park it was pointed out to me that the back left pocket of my pants looked like someone had used it as an impromptu canvas for some form of really simplistic abstract art. I don't mean a few stray marks. I mean all my backside needed was some PVC tubing and a black turtleneck and it could have jammed Blue Man Group.
Video evidence from the skate camp clips we recorded for our web page suggests the marks were not there when I showed up at the camp. Looking-at-my-butt evidence makes it pretty clear they were there a short time later.
The only one with a reasonable chance to scribble all over my rear between the time I left the camp and the time the marks were discovered is the band director at Rosemount High School. I do not suspect him.
Anyway, if anyone feels unfairly accused by this column I apologize. But a pre-teen skater with a hyperactive pen hand seems like the most logical explanation for this unexpected colorization of my kiester. In my mind it narrowly edges out other potential explanations, which range from an unseen pen hanging from the camera bag I was carrying to Gremlins.
None of which should suggest that a scribble-happy skater is an entirely satisfying explanation for the graffiti-fying of my sensible workday trousers. For one thing, the amount of drawing that was done would have taken some time. These were some serious pen marks. Put a white hat on it and my pocket would have looked right at home in the Smurf village. Just call me Vandalized Smurf.
I'd like to think I would have noticed someone putting in that kind of effort on my derriere, but it's possible I could have missed it. I had a calendar in that particular pocket, so it's certainly possible I wouldn't have felt the point of the pen as it sketched a work of modern art behind my back.
But it seems unlikely any young skateboarder would have wanted to devote that kind of attention to my pants when there were other skaters performing tricks with names like "Fakey Rock-it" or "Corkscrew Whackadoodle" or "Hey, I Didn't Fall Down This Time." Even if all the tricks looked, to me, like someone rolling up a ramp, stopping and rolling back down.
I don't get skateboarding.
With all that going on is it really reasonable to think someone would bother to take the time to attack my rear end with a pen?
To tell the truth, I'm not even that upset about the whole thing. All I lost was a pair of pants. And it gave me an opportunity to talk about my fanny in polite company. That can't be all bad, right?
I'm just confused. Outside of abduction by alien art students or marking by some trouser-related secret society I've yet to learn about I just can't figure out how this happened.
Those skateboarders seem like the most likely culprits (everyone knows kids these days are all up to no good, right?) but it's hardly an open-and-shut case. If the pen don't scribble you must not quibble, or something.
Maybe I'm just not meant to know. Maybe some mysteries are beyond the grasp of human understanding.
First Stonehenge, then crop circles and now my pants.
Yeah, that sounds about right.
Skaters, you're off the hook.

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