In a tiny bungalow live two parents and their four teenagers. But all is not as it seems. Two sisters, 18 and 15, and two brothers, 18 and 15. Younger sister ends up moving in with her girlfriend (L+L). Then they push older sister and older brother (E+D) to date, it becomes a romantic and sexual relationship, but this is not the scandal! By the end of the story, E+D are living together, having lots of sex, and even have a pile of money while they go to college.
During Christmas vacation a mother, daughter and son are turned on by the daughter's older boyfriend. While the mother gets seduced by the boyfriend, brother and sister get it on after they see what is happening between the two. The son thinks his sister is sleeping on the couch and seduces her, then finds out it was his mother. On orgy ensues when the daughter and her boyfriend come in to see what the noise is in the living room. What a Christmas Vacation!