My older sister has a big-titted, erotic body, so whenever she's feeling pent-up, she comes to my room late at night saying she'll help me with masturbation. I honestly accept her offer, but once I hear her erotic moaning, my cock gets rock hard. In the end, she pins me down, we go straight to bareback penetration, and I can't hold back—I erupt hard and she squeezes out every last drop.