My father remarried and suddenly I had an older sister. She's beautiful with a stunning figure, always lounging around in just a tank top and panties. As a teenage guy, the sight is overwhelming—I get instantly aroused. Her defenseless, plump ass right in front of me makes me lose control, and I can't help but thrust into her from behind, shooting my load inside. I know it's wrong, but it feels so good I end up doing it over and over. I expected her to be furious, but instead she said, "You're making me so turned on I can't sleep..." and started craving it every night. I'm shocked by my dried-sardine sister's insatiable sex drive.