This true story of my adorable Rebecca follows on from 'Rebecca Deliciously Unfaithfil' and 'Rebecca, Unfaithful Again.' It was the Christmas after our Cyprus holiday and Rebecca's fabulous performance with the magnificently hung Stavros. Back in England we returned to 'fantasy role play' although Rebecca did go out with a couple of other men while living with me. I always enjoyed hearing about it afterwards, even if she only snogged them, she was always such a wonderful tease, keeping me on tenderhooks before she revealed just how far she'd gone, exquisite torture! Then the Christmas party invitation, it was to her previous place of work. She had left there two months earlier for a (far) better job but still had friends there, including bitchy Emma. As the party approached I kept telling Rebecca that this was her chance to be a real 'party slut' as she no longer worked there. She teased me by going along with my suggestions in role-play in bed, she also spent a small fortune (on my credit card!) on new lingerie to go with her 'little black dress' for the party. We enjoyed a few glasses of wine while getting ready on the evening, Rebecca was being a real tease as she sat at her dressing table slowly painting her nails, trying on different pairs of stockings etc until she was happy with her outfit, it was all I could do not to wank while watching her... "You are going to tonight, aren't you gorgeous," I said "Well, thats for you to find out.." she replied.. As soon as we arrived we met bitchy Emma who could not wait to introduce Rebecca to the 'new guys' etc. I enjoyed a drink at the bar, danced with Rebecca a few times and got hard watching her dance with a couple of guys. After that I told Rebecca I was "just nipping out to the pub for an hour or so.." and told her to "have fun.." About two hours later I returned, full of apprehensive excitement at what I might find, what Rebecca may have done, who she had flirted with etc. Again, I both wanted her to have been faithful, not gone with anyone else, and also hugely turned on that she might have. Delicious jealousy. I could not see Rebecca anywhere so went to the bar, there bitchy Emma delighted in telling me that Rebecca was "enjoying lots of attention!!!" I still could not see her anywhere so ventured upstairs to where the office conference rooms etc were It was very dark but, I knew she was up there somewhere, it was her scent (Dune)...and then I heard her, the unmistakably horny moans I knew so well.. I felt overwhelming excitement,lust and yes, jealousy, this was not a holiday fling, we were in London yet I knew I wanted it to be Rebecca, I wanted her to be with another man. I looked into the office, and what a sight, it was almost dark but the light from street lamps outside illuminated my adorable Rebecca on her back on a desk, her dress up around her neck and her stocking-clad thighs around her lover. He was fucking her very hard, ramming into her devine pussy and she was loving it, wimpering with pleasure then crying out as she came. He came soon after and I saw his fat, wet cock slip out of Rebecca. I was about to move from my vantage point hidden inside the door when, my heart stopped. Another man, who I had not seen before, took his place between Rebecca's thighs and just pushed his cock straight into her. He was older, more powerfully built and he gripped her shapely buttocks, lifting her gorgeously lickable bum right off the desk as he rammed into her. This was getting all too much for me, I was openly wanking now, even as the first guy, clearly smirking, walked past me out of the room. His replacement in Rebecca's pussy was really enjoying it, slapping her bum and gripping her luxurious black hair as he finally emptied into her pussy, Rebecca came again, visibly shudering.My cum had splashed down my legs and over the door. Twenty minutes later we were in a taxi heading home, I wanted to go down on Rebecca there and then but she stopped me, aware that the taxi driver was watching and listening attentively! At home I could not get to bed fast enough, Rebecca then peeled off her dress, her thong was gone but still in her stockings she joined me, sitting astride my chest.. "Did you enjoy watching your little slut.." she asked, looking down at me.. "Oh yes, my fabulous Rebecca, my wonderfully unfaithful slut" I replied, looking up at her beautiful breasts. At that she moved her sodden pussy over my mouth and reached down to play with her clit. "You want their cum in your mouth, dont you.." she said, teasingly. "Yes, please" I managed to answer and, at that, Rebecca reached down and parted her pussy lips. What must have been at least half a cup of cum slid down and into my open, hungry mouth, as I tasted the combined cum of both Rebecca's lovers I came, without even touching my throbbing cock. It was the most wonderful, cuckold moment...Rebecca, I cannot thank you enough. Juliancuckold