Go and wash your sister's body

You look at him, giving him one last kiss before standing up. "I'll just go and clean myself, my brother should be here soon." He just nods. "We should make this a regular thing." You say to him. He looks suprised at you before saying "Sure, I'd love to." You then go up into her room. You take some fresh clothes and go into the bathroom. You put her dirty clothes into the laundry and step into the shower. As you clean yourself you suddenly get aroused by the feeling of the water running over your pussy. You think again of what you did down there: You just had sex as your sister ... with your best friend!!! By thinking of that you suddenly feel yourself getting wet again. You place one arm at the wall to stabilise you as the other hand goes down between your legs. You start masturbating again, moaning Dave's name in the shower. You soon enough feel yourself squirting all over the shower as you get your orgasm. You then finish cleaning yourself and put on her new clothes.