Thomas, caught off guard by his sister's anal request, hesitates. She persists, lubing up her asshole, which stretches around his cock as he enters her from behind. He fucks her ass gently, then brutally, slapping her cheeks, as she moans, "Fuck my ass, Thomas!" He pulls out to cum on her ass, but she quickly turns around and sucks the remaining cum from his cock, swallowing it. She then teasingly wipes his cum off her ass and licks it off her fingers, leaving Thomas breathless.