I remember a couple of years ago when I first started seriously writing, the writer boards were hot with requests for zombies. Zombies in romance? I have a very vivid imagination, but I couldn't imagine pairing my heroine with the a zombie hero. He just wouldn't have the appeal for me and instead I felt a major "icky" factor.
One of the first rules that I learned in writing romance is that writers love their heroes and hope that their readers fall in love with him also. I like my heroes dark, but a flesh eating corpse was going a little too far for me.
How about Big Foot or Sasquatch? I have yet to read a paranormal romance novel with the lead being a towering furry man-like creature and after watching "The Messing with Sasquatch" commercials, I'm not sure that I will ever find them attractive or appealing to be cast as either of my leads.
As a romance reader and writer, I can handle bloodsucking corpses with fangs and the smell of dog with my werewolves, but zombies and Sasquatch, I will leave on the shelf, for now.