A bored stepbrother and sister, Michelle and her sibling, find themselves alone and horny. Michelle starts touching herself, her fingers exploring her wet pussy, while her brother, unknowingly, enters the bathroom. Caught in the act, Michelle's anger flares, but it soon turns into desire as she fantasizes about her brother's thick cock. They decide to masturbate openly in front of each other, their lust growing until someone's arrival cuts their erotic encounter short.