The sister, feeling daring, decides to surprise her brother in the shower. As he stands under the spray, she joins him, her naked body pressing against his. She can feel his cock hardening against her, and she reaches down to stroke it, making him groan. He turns to face her, pinning her against the wall, his hands sliding down to grip her ass as he enters her, the hot water pounding down on them as they fuck, their moans and the sound of the water filling the small room.