Wild And Wicked Things by May Francesca

On Crow Island, people whispered, real magic lurked just below the surface, but Annie Mason never expected her enigmatic new neighbor to be a witch. When she witnesses a confrontation between her best friend Bea and the infamous Emmeline Delacroix at one of Emmeline's extravagantly illicit parties, she is drawn into a glittering, haunted world. A world where magic can buy what money can not; a world where the consequence of a forbidden blood bargain might be death