The old man's eyes flutter open to find his young granddaughter's head buried between his legs. She's tentatively exploring his cock, her small hand wrapping around his shaft, feeling the difference between his aged skin and her smooth, youthful hands. He groans as she starts to stroke him, her rhythm unsure but her enthusiasm evident. She leans down, taking the tip of his cock into her mouth, her tongue tentatively licking the precum beading there. He lets out a moan, encouraging her, as she starts to bob her head, her hand pumping his shaft in time with her mouth, until he can't hold back any longer, his cock pulsing as he fills her mouth with his hot cum.