Incest is an extremely common sort in Our World, for Werewolves, Vampires, etc. In Our World, Incest is mostly used in terms of relatives that want to perserve their family blood in their own families and relatives, and The Dark One even apporved of this from the beginning of time. Vampires are mostly known to have done this activity, as they have stubborn pride to maintain their royal blood status. So far, the only few people shown with this incestuous relationship are Vamwolf and Vanessa Voderick.