Vampire fan fiction has risen with book-turned-film series Twilight and hit television shows like True Blood and The Vampire Diaries rekindling our fascination with vampires. The obsession over sharp-teeth, blood-sucking creatures à la Edward Cullen or Count Dracula is not just limited to the confines of Hollywood. Some fans like real-life vampire couple Pyretta Blaze and Andy Filth (not their real names) admit they have been drinking each other’s blood for three years and believe we should all be more open-minded and educated about their ghoulish lifestyle.

“Everyone is completely vetted to check they have no mental health history and have a clean blood record,” said Blaze in an interview with This Morning. “Everyone has a full examination — mentally and physically. You pick one partner you're totally happy with and it's very safe, clean, and sterile.” Blaze and Filth confess they are extremely health-conscious about their blood swapping as they would be with sex in the privacy of their bedroom.

One thing that gets their blood boiling is the misconceptions people have about vampires due to their portrayal in Hollywood. The married couple assures viewers they don’t lurk around in the dark and only drink blood in the confines of their vampire community.

Currently, there are between 10,000 to 15,000 people part of an underground vampire society in the UK, according to Dr. Emyr Williams, a psychologist and senior lecturer at Glyndŵr University. These are normal people leading normal lives. Williams admits it has taken him six years to gain the trust of the secret society. “They know they need to consume blood. They need to consume psychic energies, but they may not like to do that,” he said on This Morning.

Williams is carrying out what is thought to be the first online academic survey in the UK of people who say they are vampires in an effort to understand vampirism. They have a psychological need to drink blood. “They are a group of people who drink blood and drain energy from people, but their well-established set of laws means they know who it can be taken from,” Williams said, The Telegraph reported.

Drinking blood may raise some eyebrows for most of us wondering if it's safe and if there are any risks. Dr. Kent Sepkowitz, an infectious-disease specialist in New York City wrote in The Daily Beast, "We ... have digestive systems accustomed to processing foods far more elaborate than blood." Blood drinkers should watch out for these infections that travel to the bloodstream: HIV, hepatitis B and hepatitis C, although it’s not clear if ingesting infected blood may result in transmission of infection. The possibility of iron overdose and toxic porphyria are other dangers.

Blaze and Filth do not have a problem stopping. “It's our spiritual connection to each other.” Filth told This Morning. “If one of us wanted to stop, it wouldn't be over."