The Devil's Plaything (1973)

In the heart of a myth-ridden, mountainous region of Germany, an impregnable, centuries-old castle--where young women worship Wanda, an ancient vampire aristocrat--casts its cursed shadow over the land. Driven by the essence of warm, bright-red blood and the power of unseen dark forces, the evil temptress forces her luscious female followers to give in to their most intimate sexual impulses, to preserve her unholy spirit. But in this hellish purgatory of perversion and blood, the accursed black sisterhood is unaware that the raven-haired leader of sin has an ulterior motive: to reincarnate in the fresh body of one of her satanic disciples.