The Devil in Mr. Holmes (1987)

Robert (John Holmes), had his problems, like all men. He just wasn't a ladies man. The only sex he got pleasure from was watching someone else. His friends could pick up women without even trying. Why couldn't John? His penis just wasn't big enough! There was nothing he could do. Why had the "Gods" betrayed him? If the "Gods" betray you, well the "Devil" can help! Just sign Beelzebub's contract and your wishes come true. In the "The Devil In Mr. Holmes" he is now the big-man around town.