Hidden away in their cramped, dimly lit room, the Brazilian siblings give in to their forbidden curiosity. The girl, her dark hair tumbling over her shoulders, tentatively traces the outline of her brother's thickening cock through his thin pajama pants. He inhales sharply, his body tensing as he fights the urge to push against her touch. Their eyes meet, and in that moment, they cross an unspoken threshold. She pulls down his pants, revealing his hard, untouched cock, and tentatively wraps her small hand around it. He gasps, his hips bucking slightly as she tentatively explores his length, her touch both hesitant and eager. Their bodies pressed together, they explore each other's virgin territories, their hearts pounding in sync as they teeter on the edge of no return.