Necromania (1971)

aka: Necromania: A Tale Of Weird Love

A couple having marital problems (the husband can't seem to rise to the occasion) visits Madame Heles (Maria Arnold), a necromancer, in hopes of improving on their boudoir blunders. After an elaborate ritual with a skull, Heles' lovely assistant Tanya first takes care of another client, then moves on to the couple, each in their turn. Once she's worked with each of them on a physical level, they are ready to meet the Madame, who will decide how best to help them. Also stars Rene Bond and Ric Lutze. (Ed Wood's lost final movie).