monogamous, polygamous?

It starts like a fairy tale: When Eva and Tom's parents meet by chance after fifteen years, there is a spark between the couple, and their offspring, who have now grown into attractive teenagers, also seem to take a great liking to each other. A friendship develops between the two families and they decide to renovate the "Waldhaus" - their children's beloved former forest kindergarten, which is now empty - and set it up as a shared weekend cottage where they can live out their erotic longings of a polygamous marriage of four. - A "fantastic dream" or a viable reality after all?