Sister Sugar by Garden Summerland

For fifteen years, Sugar Cristea has been raised by a creepy family of elderly sisters called the Serviance. They are healers; witches bound in service to the vampire royal family, the Greys. The Sisters have kept Sugar hidden away from modern society, grooming her to carry on Cristea tradition.

But for as long as she could remember, Sugar has longed for a life outside the gates of Ravenscleft where the Sisters have kept her under constant scrutiny. Then one day a local Gypsy boy wanders past the manor and Sugar is instantly smitten. He is her first boyfriend. But men are forbidden on the estate grounds, and when his body washes up on the beach a short time later, Sugar is heartbroken. Blaming the Sisters, she vows to escape her family of captors. Her salvation comes in the form of Emilian Grey, the young vampire prince who has fallen in love with her. He has been watching over her, protecting her... and waiting for her. And he will share with her the secret of her destiny - that one day, she will fulfill an ancient prophecy; this lowly servant girl shall become a queen; the Queen of the Kindred.