YMMV / Daughters of Darkness (1971)

• Complete Monster: Elizabeth Báthory is the historical countess who tortured and murdered 800 virgins to death and used their blood to be young and beautiful forever. After faking her death, Báthory used her vampiric immortality to wander Europe and and drain more virgins over the centuries. To get her victims, Báthory seduces and mind-controls mortal women to become her thralls, despite their conscious protests. After encountering a married couple, Valerie and Stefan Chilton in a Belgian village, Báthory has her current thrall seduce Stefan, knowing he's a sadist and will rape and kill her, while manipulating Valerie into replacing her and has sex with her while she's mind-controlled. Báthory then kills Stefan and turns Valerie into a bloodsucker who will carry on her ways after she's gone.

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