Kohlpiesel's Daughters (1979)

The farmer Kohlpiesel has four daughters, two of whom still have to be brought under the hood, but have little chance of a man because they are not particularly pretty. The two pretty daughters Petra and Paula never miss an opportunity for erotic adventures, but Fritzi and Franzi have just been neglected by God in terms of beauty and can only watch the wild goings-on of their hot sisters with envy. Then Kohlpiesel decides on an erotic trick. The two pretty daughters are supposed to seduce two men for their sisters - and the highly erotic confusion through all the beds takes its chaotic course.