This is a Vampire/Witch Setting
In 17th-century colonial North America, the supernatural was considered part of everyday life; many people believed that Satan was present and active on Earth. This concept emerged in Europe around the fifteenth century and spread with colonists to North America. Peasants used a kind of witchcraft to invoke particular charms for farming and agriculture. Over time, the idea of white magic transformed into dark magic and became associated with demons and evil spirits. From 1560 to 1670, witchcraft persecutions became common as superstitions became associated with the devil.
Men and women in Salem believed that all the misfortunes could be attributed to the work of the devil; when events such as infant death, crop failures, or social friction among the congregation occurred, the supernatural was blamed. Bridget Bishop was the first person executed for witchcraft during the Salem witch trials of 1692. She had been caught performing a ritual sacrifice while doing blood magic. And blood magic was considered to be one of the darkest forms of magic. Sadly such ritual cost the lives of two villagers. The wife and small child of a well respected man of the town. But no one knew she left behind a daughter.
The Bishop family sometime in the late 1700's fled Salem and New England to the south for sanctuary. They eventually settled in the thriving Louisiana city of New Orleans in the section that was known as the French Quarter. A place where those who claimed to be psychics or know all forms of witchcraft could be found.
The year now is 2014, centuries have passed since the Bishop family settled in the big city. Eventually changing their last name to Perkins so there would be no connection to them from the historical events. It didn't take them long to realize they were being hunted by someone, or something due to the ritual performed centuries ago. So changing their name was also a way for them to hide themselves.
Ginger Perkins, a thriving young woman at the ripe young age of only twenty five was a proud descendent of Bridget Bishop. She knew her family history despite her family being against her knowing cause they feared for her safety. As decades passed the Bishops/Perkins stopped their use of magic. Trying to deceive not only others but themselves that they were just normal everyday people like everyone else. Ginger however learned the truth in school growing up. And then decided to research her history and bloodline.
New Orleans however wasn't like it was centuries ago. Witchcraft now seemed more, well, Hollywood than real. The French Quarter more a tourist location than anything. True witchcraft in the eye of the human race didn't seem to truly exists. Except for a select few, and Ginger was one of those few. And if a person truly wanted to find a witch, they'd know what dark corners of the French Quarter to go too. And the small group of true witches considered Ginger almost their leader. Not only cause of her bloodline history, but she also seemed the most powerful. Delving into both white and black magics.
I'm thinking your character would be the Vampire. Perhaps the man who's wife and child were sacrificed and now through the centuries he's destroyed or tried to destroy the Bishop family bloodline out of revenge. I kinda see this as a game with bdsm, power struggle, perhaps eventually turning into a dark romance over time.