Robby, the insatiable gym rat, can't keep his eyes off his stepsister, RubiRay, as she prepares for her workout in their shared bedroom. She's a vision in her form-fitting yoga pants, her ass and pussy clearly outlined. He can't help but stroke his massive cock, fantasizing about fucking her right there on the bed. As she bends over to tie her sneakers, he seizes the moment, pulling out his cock and cumming all over her yoga pants. The cum seeps through the fabric, creating a visible wet spot. Rubi, unfazed, pulls her pants up, ready to hit the gym, leaving Robby to dream of the next time he can fill her pants with his cum.