That is absolutely ridiculous.
Like people have said over and over...if it were 2 guys trying to strip a girl, it would DEFINITELY be a violation. Saying that the boy should've liked it is just as stupid. Imagine if you're trying to mow the lawn and crap and suddenly two maniacs come up to you, pin you down while you don't WANT them to pin you down, and take off your clothes for no reason whatsoever. You might think it's sexy, but it's not. That's like saying a boy should be delighted if a nude woman was chainsawing him in half. A bit exaggerated example, but that's pretty much what people are saying.
Again the justice system proved how discriminated they are towards age, gender, race, ethnic, and other groups when it comes up to a similar situation. And anyways, the boy freaking screamed out for help so they could stop but they didn't stop. Not only that, a whole video of his humiliation was posted on fucking Youtube. If that isn't enough, he's only 11 and the girls got away with it. What the hell were the fucking police thinking? That it was just a prank? It maybe was, but just because it was a prank doesn't mean that it was funny to almost everyone or even the slightest bit justified.