Due to a unique disease, Rosalyn Sphinx experiences uncontrollable orgasms that she is unable to stop. It's difficult for her to live with her stepbrother Lucas Frost because he gets aroused every time Rosalyn cums in front of him. One day, Dick Chibbles, Lucas's father, notices that his stepsister is staring at him with dreamy eyes in the living room. Fearing that Rosalyn could start to believe that fucking could be the solution to her problems, Dick kicks Lucas out. But as Dick nods out in front of the TV, Lucas slips back into the living room, only to be delighted to see Rosalyn doing exactly what Dick had thought she would. Rosalyn sdeep throats Lucas's fuck stick till he gets nice and hard as they begin in the living room. As Dick is still asleep, Rosalyn decides to take a chance and jumps from the couch onto Lucas's hardon in order to ride him. Dick is too close for comfort, even if her body enjoys how Lucas fills her up to her fullest. The stepsiblings head to the bedroom, where Rosalyn settles down on the bed and invites Lucas back in after dropping their abandoned garments on the floor. Fucking his extremely slender stepsi is all Lucas could possibly want for. He relishes the chance to mould her ass with his large hands and hits her from behind when she rolls over onto her hands and knees. Dick storms into the room just as he is about to cum all over Rosalyn's ass. He saw the clothing on the floor when he woke up from his siesta, and he knew just what his out-of-control kids were getting up to.
