|Bloodsucker ... Julia Caples poses with 'donor' Wesley Hendricks Laurentiu Garofeanu / Barcroft Media|
She meets fellow vampire enthusiasts at a local occult and oddities store where she cuts them with a pagan-style knife before lapping up their blood.
She believes it keeps her young and vigorous, just like the ageless bloodsuckers from movies such as Twilight.
The blood-thirsty care worker claims there is a huge sub-culture of blood drinkers across the world.
But she is trying to keep her strange hobby away from son Alexi, 11. And daughter Ariel, 24, hates her mum’s obsession – urging her to stop.
Julia, from Wilkes Barre, Pennsylvania, US, said: “When I feed off of a person and drink their blood I feel stronger and healthier.
“I know scientifically there’s not a lot of nutrition in blood, but maybe there’s some value we haven’t discovered yet.
“I feel more beautiful than any other time when I’m regularly drinking.
“I’m also extremely healthy with no major health problems, and I have an abundance of energy all the time.
“At times I’ve drunk half-a-gallon a month.”
Julia’s fascination with blood began as a young girl, during her first kiss as a teenager, when she got the urge to bite her sweetheart.
She said: “It was my natural instinct and I liked the taste. I just got an urge and can’t really explain it. It’s never gone away.
“Needless to say though, he never kissed me again.”
But Julia did not start drinking blood regularly until she met her now ex-husband Donald, 49.
Counsellor Donald and Julia got married in a vampire-themed wedding in October 2000 and even drank from each other to celebrate.
The pair became part of a sub-culture of vamp fans who visited New York nightclubs and drink from each other.
But when the pair had son Alexi, Donald vowed never to drink again.
He said: “I gave up, so Julia didn’t have to. We agreed that one of us would need to stop and focus on parenting full time.
“Julia still likes to drink, but she’s also an amazing mother, and her children come first. She’d never let it stop her mothering her kids.”
Despite his mum’s efforts to keep her lifestyle secret from him, Alexi is beginning to suspect his mum’s ghoulish ways.
He said: “We have all these decorations at home like coffins and dolls. I’m starting to think she’s a vampire.”
And Ariel said: “I think she runs a lot of health risks. I worry she might get a disease from someone through the blood.”
Julia, who blogs about vampirism using her online persona Lady DarkRose, says she’s aware of the health dangers, but all her donors are tested before she’ll drink from them.
She added: “I meet some donors online but I absolutely have to meet them in person first.
“And they have to get blood tests to make sure that they’re not carrying any blood-borne diseases like AIDS or HIV.”
Haematologist Steven Gruenstein, from the Mount Sinai Hospital in New York, said:
“There are risks involved. HIV, hepatitis and other viral and bacterial illnesses can be transmitted through blood, so though these risks are not large, they are real and it would be an unnecessary danger.
“Blood does contain chemicals like salt, iron, protein, and people might be driven to drink it because of a deficiency of iron or some other chemical.”
He added: “There has been a resurgence of cult drinking blood vampirism in this country and throughout the world, possibly down to all these TV shows and movies that have become so popular.”