It's all about the blood. From the mutated DNA strands that bring the animal to the surface in shapeshifters to the diseased cells that create zombies, it's always coursing through our veins. Is there anything more intimate than sharing blood? Before you say "Gross!" and click away, think about it. You are literally giving your life force to another person. You are trusting someone to know how to keep you safe while they fulfill their desires, or even their needs. There is so much more to it than just preventing the spread of diseases from donor to drinker, although that's always a consideration.
Blood is most commonly associated with The Big 'V'. Vampires. We love them. We know all about them, right? The shapeshifting ones, the emo ones, the Viking, and the sparkly.
But what about vampyres? The real ones? The ones who consume blood or energy regularly? They're out there, keeping their compulsions hidden from society at large.
Blood fetishists use blood for sexual arousal. The sight of it, the taste, the smell, the feel. Bloodplay is usually kept within the confines of a 'scene'. It gets them off. It's mostly sexual, but the trust and bond cultivated between the parities is undeniable.
Sanguinarians (sang) have a need to feed on blood. They do it because it nourishes their physical being and replenishes their emotional energy. Without it, they can develop migraines, weakened immune systems, depression, and even joint pain and rages. It's a part of their nature, not some image they wear, and it's not a sex game to them. Some of these sangs have suffered these symptoms for years only to have ingesting blood provide nearly instant relief, leaving the sang relaxed or energized. Is it medical, or a psychosomatic response? Does it matter?
There are several medical conditions which may have contributed to the myth of vampires. Porphyria can cause a sensitivity to UV light and tightening around the gums, making the teeth seem longer than normal. Garlic can exacerbate the symptoms. Noticing any vampire myths yet?
Xeroderma pigmentosum causes severe photosensitivity. Exposure to the sun can cause blistering, and sometimes even death.
Some sufferers of catalepsy, a disorder that causes muscle rigidity, may have been buried alive. When they recovered from their symptoms, they might have attempted to dig themselves out of their graves. Exhumation of these bodies found bloody hands and mouths. The traditional method of driving a stake through their hearts to kill these vampires most likely simply released gasses trapped in the abdominal cavities of these corpses, leading superstitious villagers to believe they had killed a member of the undead.
These undiagnosed, misunderstood conditions probably gave birth to the myths we see propagated by movies and books today. Is it any wonder why these vampyres prefer to stay in the coffin?