Origins is not a standalone series. All characters, events, places and themes are canonical to the Vengeance series universe. These stories are not essential to the understanding of the character(s) as they are portrayed in the main series but can assist by shedding light on where they came from and what they have been through. These stories are meant to be consumed after reading Vengeance: Children of Faust, first. Having a reference to past events prior to reading along book one may lessen any mystique and curiosity that is being established in the narrative.