If you've spent any time on popular news sites over the past few days, you may have come across the bizarre story out of Wisconsin about a 12-year-old who was stabbed by her classmates. While this is one of those things that are shocking on their own, it's made weirder due to mentions of "Slenderman" by the attempted murderers.

Of course, this led to everyone and his mother racing to explain to a confused general population just what Slenderman is, even though he's had a Wikipedia page since August 2012, had a Fox cartoon made about him, was a monster of the week (kinda) on Supernatural three months back and you can find Slenderman costumes in all reputable costume shops.

Okay, so maybe those references are still a bit obscure -- Supernatural is still a CW show, after all -- but it's still kind of funny watching CNN and the like using the same bits of information from the same sources to pretend they're up to speed on the Slenderman phenomenon. While they can certainly rewrite the same three facts with the best of them, none of them have been able to speak to why the creature is so popular with the Internet.

"Creature" is a very deliberate choice of word on my part. I get why you might be inclined to refer to him as a character, but the reality is that Slenderman is no different from the vampires, werewolves and zombies of popular folklore. Yeah, he's a fictional creature, but unlike the Freddy Kruegers, Godzillas and Xenomorphs of cinema, he wasn't created to push a product. He was simply created, and then the Internet took him and made him their own.

As a creature of folklore, he came along at the right time and, even though Eric Knudsen didn't know it when he posted the first photos of Slenderman to Something Awful five years ago, was just what the Internet was waiting for.

I attribute his continuing success to three things.

1. He's got the look. Sure, he's got a popular costume because putting together a Slenderman outfit is only one difficulty step above that awful "Clark Kent in a suit with a Superman shirt on under his button-down" outfit that's become a thing, but it's more than just being a great lazy costume. Slenderman falls right in the middle of the familiar horror/unknowable horror scale.

I mean, there's definitely something weird about a creature with overlong limbs and, depending on the interpretation, tentacles. Those are not things you just look past. But they're not things that are so horrifying that they either look too silly to be scary or too weird to be irrational. You can look at Slenderman and know immediately that it's something horrifying, which means the terror is immediate. He's not going to break your brain the way a Lovecraftian horror will; he's just immediately going to make you panic. It's what makes the first Photoshop (above) a classic of photo manipulation: You don't have to struggle to find what's wrong because what's wrong is a slight break in reality, which is really among the scariest breaks there are.