Night Visitors: Sex Hunt(1979)

In a remote rural town lived two men: Gyoromatsu Hashishita, renowned as a master of nighttime visits, and Senkichi Nitta, a novice. They would sneak into various houses and enjoy having intense affairs with all sorts of women around the town. One day, as usual, Senkichi was hurrying towards his new target house under the moonlight, but he was restless. This was because his target for that night's visit was Oyuki, the woman he was deeply in love with. A romantic porno depicting the fate and hard-ons of these genius nighttime visitors.