Though it's already listed as being connected with Woody Allen's Annie Hall, which shows The House of Exorcism as a twin-bill on a marquee, it's actually worked into a visual punchline since Woody's character, Alvy Singer, hates Los Angeles, and jovial Christmas music plays while this marquee, along with Messiah of Evil is shown, is shown, representing Alvy's feelings.
The sex scene between Sylva Koscina and Gabriele Tinti in Lisa and the Devil (1973) is repeated here but extended with a long sequence shot by producer Alfredo Leone and using body doubles.