As explained by Aiden on his date with Vivian, who is still unaware of her heritage during the scene, the species of werewolf that appears to be present in the film are not the traditional werewolf but a loup-garou. They do not require a full moon for a metamorphosis, they can transition at will to their alternate form. They are vulnerable to not only silver but fire as well. They cannot transfer a werewolf curse through bites or scratches; you have to be born with your powers; they are not obtained.
The title, Blood and Chocolate, is a metaphor for Vivian's predicament in the film and novel. She must remain loyal to her family heritage, her family "blood", and resist the temptation of a normal human relationship with Aidan, the "chocolate". Her cover up for her true lineage is as a chocolatier who serves gourmet desserts in a small shop while her secret identity is as a werewolf with loyalty to her bloodline, her human identity being chocolate and her secret identity being blood.
Agnes Bruckner is the only American actor in a cast otherwise entirely made up of European actors.
All works, covers and illustrations attributed to Aiden belong in real life to the Spanish graphic artist Victoria Francés.
All of the scenes involving wolves, were shot on sets designed and created by Production Designer Kevin Phipps. These include all of the Forest, Creek and River settings, the Interior of the Chapel, the Hotel Bedroom and Absinthe Factory. These sets were all constructed on the sound stages at Media Pro studios in Bucharest, Romania.
The book was originally adapted into a script by Christopher Landon, whose father Michael Landon had a leading role in the film I Was a Teenage Werewolf (1957).
Since 1997, five directors were in talks to film Blood and Chocolate, namely Larry Williams and his wife Leslie Libman, Po-Chih Leong, Sanji Senaka, and Rupert Wainwright, before Katja von Garnier finally signed in January 2005 to direct the film.
Third collaboration between Katja Riemann and Katja von Garnier after Making Up! (1993) and Bandits (1997).
"Ulf" is Norse and means "wolf". Both words are cognates and share a common linguistic origin.
Author Annette Curtis Klause was not kept up to date by the producers of the film. She had to find the information about the filming on the Web.