The luxurious call girl Maria hides the source of her income from her three younger sisters, whom she looks with almost maternal care, and whom she falls asleep with gifts at the end of each of her “missions”. But soon she notices that, despite the moral commandments, for which she spares no time, passion smolders between the thighs of three young girls who cannot wait to become addicted to the joys of sex in the company of neighboring "stallions". They kept it secret. Maria also finds their own father, secretly playing forbidden games with the participation of depraved and accessible young women. Then, to even greater confusion, the rich Giovanni asks her to marry him ...