In the dimly lit room, the sister's breath hitches as she takes in her brother's enormous cock, straining against his jeans. She's never seen anything like it, and her curiosity piqued, she reaches out, tentatively touching the bulge. He tenses, but she's undeterred, unbuttoning his jeans to reveal his throbbing dick. She licks her lips, her pussy aching with need. She wants it, all of it, and she's not afraid to take it. She guides him to her, feeling his length slide inside her, stretching her, filling her completely.