This story was okay. I was amused and pleased that the vampires were still pretty much lame teenage boys, but with some weird appetites. The grossout went a bit too far for me, though--I didn't really find it humorous or horrifying, just gross. That being said, though, the menstrual blood cure explanation made this world's vampire's somewhat more plausible than typical vampires. I generally don't find vampire's very plausible because when there is an outbreak on a story, the condition is pretty much viral. If you don't stop it when there's only a few you won't ever stop it (I've never found the concept of killing the head vampire to kill all his progeny at all plausible). The menstrual blood cure gives a reason why the vampire plague isn't unstoppable--because at any given time there are menstruating women out and about, and if the vampires are lured to their cure then even if they have a sudden population explosion it will probably resolve itself within a few weeks instead of becoming unstoppable.
Having seen more vampire movies than I can remember, and read about two bookshelves worth of books, think I feel qualified to respond to this.
See, I have developed a theory that accounts for the existence of vampires. Actually, it's two theories, and nearly every vampire story fits into one of them.
1. First there is the fantasy vampire story. This is the story that explores vampirism along the fantastic route. These vampires are a sort of demon or some other creature from outside our physical plane of existence. Hence they are susceptible to non-mundane weapons: religious symbols (most often crosses, but in some cases other paraphernalia from other religions work), running water and killing the sire kills the underling. It's metaphysical, and only needs to make "sense" within itself. Two popular examples for this type of vampire are the Buffy series and Van Helsing (the movie and Bram Stoker's book Dracula).
2. Then there is the scifi vampire. These vampires are the victim of parallel evolution, a parasite or even modern experiments. Whatever it is, there is a scientific explanation for the vampires powers and weakness. A different physiology (whether it came about naturally, via a parasite or through mad-scientist-tinkering) would explain many things, since we see them in other animals in nature: the need to drink blood (mosquitoes), aversion to sunlight (moles) allergies to garlic and/or silver (humans). These stories make their own sense as well. Two popular examples: Underworld, Blade.
It is important to note that in both types of vampires there are explanations for why the entire world isn't overrun. Be it the Buffy-verse vampires who only turn people when they want to or the Underworld-verse where the parasites more often kill the victim than turn them.
Also, one will almost never see the second type of vampire flying, but will see the first type flying.
And that brings me back to our story. Where does it fit?
On the one hand, an STD that turns people into vampires and doesn't morph their physiology (prosthetic teeth) fits the second type of vampire. The cure also jives nicely with that, as well with the stereotypical vampire being attracted to women in underwired nightdresses. On the other hand, these dudes can fly and we're hearing about them from our tentacled flying castle.
But then there's the deal with a poked vampire bleeding smoke, not blood. That, in my opinion, is the clincher. These are fantastical vampires. Such a drastic change in the person's body is usually the manifestation of demon infestation or other-worldly habitation. And if the method of infestation bothers you and doesn't fit nicely with that, just ask any religious person, they will tell you that their god works through the natural world. So why shouldn't demons?
Aside: "vampirism" should be a real word and there is no excuse for it not being in my spellchecker's dictionary.
