Bored and alone, a brother and sister turn to self-pleasure, unaware of each other's presence. She masturbates in the bathroom, fingers deep in her wet pussy, while he overhears her moans. Catching her off guard, he finds her naked and vulnerable. They argue, but later, they decide to masturbate openly. Her eyes widen at the sight of his thick, straight cock. As they're about to act on their mutual desire, an interruption forces them to halt their erotic encounter.