Best friends girlfriend - watch but don't touch.

Sadie insisted that I watch but don't touch. I sat at her dressing table and watched fascinated as she opened her knicker drawer. "I'm going to show you how I do myself and you're going to watch," she quipped pulling out a silk G-string. . She slipped out of her robe and pulled her thong tight and snug over her quim. Next she rummaged deep in the drawer and found an old bra. Taking a pair of nail scissors she cut 2 holes for her nipples to poke through. It was a bit small for her now, but unperturbed she forced her tits through the holes she had snipped and did it up. Then she knelt on her bed and instructed me to lie down on it. She was straddling me, her thong-clad cunt inches from my face. The moisture beginning to seep through the ivory silk. "Don't you dare touch me," she teased lowering herself within licking distance. I could smell her heady aroma now. She pulled on the G-string and it disappeared between the lips of her neatly trimmed cunt. Meanwhile she pulled and tugged at her nipples which had protruded thru her bra, moving her hips back and forth almost brushing my lips. I couldn't work out how she could get so close but so far, then I realised she was watching herself in the mirror. She leaned back reaching under her pillow and grabbed her dildo and put the pillow under her bum. As she did so more wetness seeped through her gusset and dripped a little onto my face. She put the hand end of her dildo into my mouth, it was obvious what I had to do.. I held it firmly between my lips and she pulled the by now soaking crotch of her string to one side and lowered herself onto the ribbed plastic cock protruding out of my mouth. I watched fascinated as it disappeared inside her. She let out a deep moan as she did so and as it went in she began to buck her hips all the while getting closer to my face as it went further in. " I bet this really turns you on" she gasped. I realised she could see my real erection vainly straining in the air. " you really want to touch me don't you? Well you can't. I'm your best mate's girlfriend and I'm not going to fuck you. You'll just have to wank over the memory of this." By now her tits were bouncing grotesquely out of the holes in her bra. Something about what she said sent her over the edge and suddenly she lost control and ground down on the dildo burying it all the way inside her and forcing her trembling clitoris onto my lips. I didn't have any choice and neither did she. I was swamped by her fluids as she came over my face, soaking her tiny G-string and filling me with her horny scent. After it was over she flopped back on the bed gasping. "That never happened - never tell your mate. Usually I'm quite happy doing that on my own in front of the mirror but I have to admit it did really turn me on." My hard on was pulsing and I was aching to do something about it. She could see that.  "Sorry I really can't do anything about that" she sighed. Then she pulled off her ruined knickers and as an afterthought flung them at me-"Here you can have these, you might find them useful." She got up and went to the bathroom.