I think I'm writing a horror story. Honestly, I don't know, because I'm not really sure what is and isn't horror any more, when it comes to fiction.
There used to be a horror section in the bookstore. I was allowed to go there the year I turned 13, after the summer in which I tore through every serial killer book in the library (Ted Bundy, the Manson family, Saucy Jack, I read everything I could get my hands on) and suffered no apparent ill effects. I bought my first Stephen King (The Eyes of the Dragon, what was not horror, I'm pretty sure [and is now lost, as with so many of my other Stephen King books - some of which were first editions, dammit! - thanks to Evil Movers]) and then my second, It, which definitely was.
If you ever meet my sister, ask her about the time I nearly killed her with the fireplace poker while I was reading Pet Sematary. Of course, she reads horror, too.
Somewhere along the line, though, there stopped being a horror section, and I had to wander around to find King, or Straub, or Kiernan. I read something the other day (I cannot remember where) that described The Graveyard Book as "the horror novel that won the Hugo." I wouldn't call The Graveyard Book horror, except for maybe the opening chapter, but I found it in the "Young Readers" section when I bought my copy. The one book that's ever scared me so badly I couldn't finish it (Joe Hill's Heart Shaped Box, for those keeping track at home) was in the Literature section.
My point is, I don't know what horror looks like any more. Vampires sparkle, werewolves have six pack abs, and Eliza Bennet slays zombies. None of this is necessarily a problem, except when you're writing something, and you want to know if you're doing it right. (Or, you know, what markets to send it to, in hopes of actually selling it.)
Writing it scares me. Maybe that's enough.