Sarah, alone in the dimly lit room, spots the bulge in her stepbrother's pants. She licks her lips, her heart pounding. He's oblivious, engrossed in his game. She inches closer, her hand trembling as she reaches out, gently tracing the outline of his massive cock. He jumps, startled, but she shushes him, her eyes locked onto his. She unzips him, her breath hitching as his cock springs free. She wraps her small hand around it, feeling its throbbing heat. She strokes him, her grip firm, her pace steady, until he's groaning, his hips bucking.