As the rain pours outside, a brother and sister seek refuge in the attic, their bodies pressed close in the dim light. The sister, her eyes wild with lust, takes the initiative, pushing her brother onto the old mattress and straddling him. She grinds her wet pussy against his hardening cock, their breaths hot and heavy, the air thick with the scent of sweat and desire. He grabs her hips, thrusting up into her, their bodies slippery with rain and lust as they fuck like animals in the storm.