What happens if a werewolf bites a vampire? What's the minimum daily requirement of blood for a vampire? Can you get zombified by having sex with a zombie?
What happens if a werewolf bites a vampire? Or vice-versa?
If you assume a vampire has the same caloric/nutritional requirements as us mortals, how much blood would they have to suck each day?
If you have sex with a zombie are you at risk of becoming one?
Jeepers, Steve. Sounds like the dating scene in Wichita leaves a lot to be desired.
Reliable information about the undead isn't easy to come by. Browsing in PubMed, the online medical database, we come upon an article in the September 2004 Biomedica by one E. Escobar Cifuentes entitled (in translation) "Rabies transmitted by vampires." This sounds promising, and reminds us, moreover, of an aspect of the problem that has been sadly neglected. On close reading, however, it turns out the varmints in question are vampire bats.
Science having let us down, we're obliged to seek insight in legend and art, the latter admittedly somewhat loosely construed, e.g., the work of George Romero. Take the matter of vampires vs. werewolves. The literature and films of old rarely mention the two in the same story, although they appear to have much in common. They share some physical traits, such as pointed ears and animal-like appearance. The old Slavonic word volkodlak, which translates roughly as "wolf hair" or "wolf mane," means "werewolf" in most places but "bloodsucking revenant" (vampire to you) in Serbia. Tradition there has it that when a werewolf dies it rises again as a vampire, and that eating the flesh of a sheep killed by a wolf meant turning into a vampire after death. Finally, we know that vampires can take the form of a wolf and summon wolves to do their bidding.
Despite this seemingly close relationship, encounters between vampires and werewolves are largely limited to recent literature and movies, e.g., the Anita Blake novels, the Underworld movies, and the Marvel comics featuring Nina Price, Vampire by Night. No disrespect, but who do you think has a better handle on the undead, pimply-faced comics auteurs or medieval Serbs? Taking Balkan lore as our starting point, therefore, we deduce that vampirism is the next stage in the werewolf's natural history, death being the lycanthropic equivalent of a caterpillar's cocoon. Interesting as this may be from a necrobiological standpoint, it lowers the dramatic stakes. A werewolf nipping at a vampire? All you'll likely get is a cranky vampire - traditionally lycanthropy is transmitted by magic or curse rather than bites. A vampire who fatally bites a werewolf, meanwhile, merely hastens a metamorphosis that would have occurred anyway. And for what? Sucking the lifeblood of an innocent maiden is one thing. Going after a slobbering beast, on the other hand, makes you think: dude must be hard up.
Next, nutrition. We know vampires drink a lot of blood - they're often described as engorged with it after feeding. But how much do they really need? Assume a six-foot, 170-pound male vampire has a base metabolic rate of 1,800 calories per day. He sleeps two-thirds of said day but must adopt an active lifestyle by night in pursuit of hemoglobin, so add 2,400 calories. The energy required to turn into a bat, wolf, mist, etc, hasn't been clinically established but, judging from sparing use of the trick in Bram Stoker's book, must be substantial - say, 2,000 calories nightly, for a total daily requirement of 6,200 calories. A unit of blood (450 milliliters) contains about 600 calories; individuals typically hold 4,000 to 6,000 milliliters, giving us a potential of 5,333 to 8,000 calories per victim. A methodical vampire, then, could easily get by with one well-drained victim per night. Indeed, given the number of people nowadays who look like they'd be happy to socialize with the Dracula crowd, it's surprising you don't see more vampires with a weight problem.
Finally to the risks of zombie sex. Much depends on what type of zombie we're talking about. Traditional voodoo zombies are dead people animated by a shaman, so you're only in danger of becoming one yourself if you die, after which you don't care anyhow. "Real" zombies, as investigated by Wade Davis, author of the controversial 1985 zombie study The Serpent and the Rainbow, arrive at their state upon being given two drugs - one to induce paralysis and another to create a disconnect from reality so they can be controlled. You could have sex with somebody in this condition; among a certain subset of men, in fact, it remains the default romantic strategy. But predators of this sort generally take care to remain unzombified themselves.
Movie zombies are another matter. Judging from the Romero oeuvre, zombie infection is spread by bites and other wounds. Abrasions during sex aren't uncommon, so condoms would be in order. Then again, Steve, we can't ignore the possibility you've misdiagnosed the problem. Who knows - with a little more finesse on your part, maybe next time she'll wake up.