Bored and horny, a brother and sister start masturbating together, the sister fingering her wet pussy while her brother strokes his thick cock. Caught in the act, they argue, but later reconcile and decide to openly masturbate in front of each other. The sister, entranced by her brother's massive dick, fantasizes about feeling it inside her. Just as they're about to act on their mutual desire, someone enters, forcing them to abruptly stop.