Among the Living Dead aka Christina, princesse de l'érotisme (1973)

Among the Living Dead aka Christina, princesse de l'érotisme (1973) : A girl arrives from London to visit her estranged relatives in a remote castle for the reading of her father's will. After a while she discovers that they are all in fact dead and her decision to live with them turns into a nightmare. Unable to leave she's drawn into a macabre underworld through visions of nude satanic rituals and her own impending sacrifice.