In the first book, Bianca, trying to defend Raquel from Mrs Bethany in English class, points out some reasons why she doesn’t like Dracula (which is about vampires) and prefers The Turn of the Screw (which is about ghosts…maybe). In the end, Bianca rejects becoming a full vampire and embraces becoming a wraith.
Vampires are mentioned as not having blood that flows in the same way as a human's (due to being undead). However, male vampires are clearly shown to be capable of having sexual intercourse, which requires some form of blood flow.
