The air is thick with tension as the siblings find themselves alone again. The sister, dressed in a revealing nightgown, can't keep her eyes off her brother's muscular frame. He catches her staring and, with a mischievous grin, starts to strip. She watches, mesmerized, as his cock springs free, already hard. She tentatively reaches out, wrapping her small hand around his shaft. He groans, encouraging her to explore his body, leading to an intense, forbidden fuck session.