Bored and frustrated, siblings find themselves alone and tempted. The brother, jacking off in his room, hears his sister's muffled moans from the adjacent bathroom. Caught in the act, she's embarrassed but intrigued by his throbbing cock. They argue, but the tension is palpable. Later, they return to each other, naked and hungry. She watches him stroke his thick, hard cock, imagining it inside her. Just as they're about to cave, a noise startles them, leaving them breathless and unsatisfied.