A brother and sister, both horny and alone in the house, decide to indulge in their secret desires. She strips down to her lacy bra and panties, her nipples hardening at the thought of his touch. He watches her, his cock tenting his pants as she spreads her legs, giving him a tantalizing view of her pussy through her sheer panties. He unzips his pants, his massive dick springing free, and they both begin to masturbate, their eyes locked on each other's bodies, their pleasure building with each stroke and flick.