Fucking the wrong sister of her lover and the ending
David’s grip tightened on his sister’s breasts, like holding on for dear life. He buried his head in her hair. And then, again, his whole body began to shake. Not a trembling like before, but great violent fits. His sister started shaking with him. Tried to hold her body in control. The more he built, she built. The more she tried to hold still, the more her body began to overwhelm her.