Spermula

Spermula is a French softcore fantasy film from 1976 made by painter and film director Charles Matton. The film was later reedited and dubbed in English as a sciencefiction comedy.

They take up residence in a huge mansion, whose neighbors include the towns mayor, his unhappy and abused wife, his venal, social climbing assistant and a fat and frustrated widow who has incestuous designs on her lazy son.Gradually Spermula and co. draw together the strands of the plot that finally ends in a huge orgy in which everyone gets what they want or at least what they deserve. Unfortunately, the women become corrupted by this contact with the outside world and their beautiful leader, Spermula, falls in love with a young artist and sacrifices her immortality for a night of passion with him. ........

Source: Wikipedia