Let Heather use you

You let her push your finger into her tight, wet snatch. She's really wet, and your fingers go in easy. Heather shudders as she uses your fingers for her pleasure. After a few strokes and a loud moan from her, Heather shifts your fingers to rub on her clit. You decide to just let her continue to use your hand as she pleases. Heather closes her eyes. After a minute of rubbing and moaning, she plunges your fingers back into her pussy, gasping. You are really getting off on your girlfriend's sister using your hand for sex.

She switches back to rubbing her clit, and your fingers are slick with her lubrication. She's humping her mound up into your hand, then suddenly squeaks and shudders as she starts to come. She pushes you back inside her as her orgasm rocks her. Her fluids increase in quantity and cover your hand. After a minute or so, she slumps back on the couch. Then she pulls your hand from her quivering cunt, and puts your fingers at your lips. You look down and she's looking back at you with a languid, satisfied look that sets your blood on fire.

You lick your fingers, then suck three into your mouth. She smiles and moans as you clean your whole hand of her slipperiness. She tastes rich and musky.