As the holidays descend, so do inhibitions. A curious stepsister, left home alone with her mom and stepbrother, starts exploring her taboo desires. She catches her stepbrother's eye, and they can't resist the pull. They start with tentative touches, graduating to aggressive petting and rough fingering. Meanwhile, mom, overhearing the commotion, joins in, eager to please her family in more ways than one. This holiday threesome is anything but traditional.