A brother and sister, caught in a moment of reckless youth, decide to spice up their usual jog by racing each other to the finish line, with a twist. The sister, wearing only a tiny pair of shorts and a sports bra, confidently struts ahead, knowing her brother can't resist the view. He, in turn, uses every opportunity to grab a feel, making their run anything but innocent. As they reach the end, their competitive nature takes over, leading to a heated argument that quickly escalates into a passionate, taboo encounter.