There is no real evidence of supernatural, immortal, shape-shifting vampires, which are derived from popular media. However, there are certain groups and subcultures that attempt to cultivate vampire-like traits, including lifestyle vampires, sanguine vampires and psychopathic vampires.
Lifestyle vampires attempt to mimic the attitudes and practices of fictional vampires. Often associated with the Goth subculture, lifestyle vampires take power from the dark, mystical side of life. Though they make no claims to possess supernatural powers, these individuals arrange their lifestyles around concepts taken from vampire fiction.
More than just costuming or play acting, lifestyle vampires often divide themselves into clans and covens modeled on fictional sources. They may attempt to avoid sunlight and engage in rituals taken from vampire media. For many lifestyle vampires, the culture serves as a source of spiritual fulfillment.
Sanguine vampires take the lifestyle one step further and engage in the practice of drinking blood. Rather than drinking whole glasses of blood, sanguine vampires typically just add a few drops to other beverages. Occasionally, they engage in actual bloodsucking, making a minor cut on a willing donor and drinking the small flow of blood. While many sanguine vampires claim to need blood, this craving is likely psychological rather than physical.
In extreme, isolated examples, some serial killers have consumed the blood of their victims, including Peter Kürten, "The Vampire of Düsseldorf," and Richard Trenton Chase, "The Vampire of Sacramento."