My mate Trevor works abroad for long periods of time so had asked me to keep an eye on his missus Gwen.Last month she knocked on the door asking if she could use the washing machine as hers had broken down.I told her to be my guest and that if she wanted I would pop over later to take a look at it save calling out a plumber. While I worked in my study I could hear Gwen beavering away in the kitchen.About mid morning she called up and asked if I wanted a coffee,I said ok and would come on down.Over coffee I was rewarded by a show of her sexy underwear as she removed and folded it neatly in her washing basket.I said that Trevor was such a lucky man to have a wife who dresses in such beautiful lingerie.Gwen blushed and asked if I could keep a secret,Trevor hadn`t even seen that underwear,she only wore it to cheer herself up when she went out on the town with her sister on the pull as she was very lonely with Trevor away all the time.I asked if she had ever gone any further on her nights out but she said no.With her washing completed she began to pack up but reminded me of my promise to call over later to look at her machine. About 19:00 I knocked on the backdoor and let myself into the kitchen.Calling out Gwen said she was upstairs and would be down shortly.I was working on the machine when Gwen came into the kitchen,she was wearing a short satin bathrobe.Gwen sat on a stool directly opposite to where I squatted on the floor,it became clear she was wearing stockings and suspenders as the robe fell away from her legs.Knowing I was staring she crossed her legs exposing the bare skin above the stocking tops.I asked if she was trying to seduce me hoping that she was.Standing up she moved over towards me,undoing her robe and letting it fall to the floor.I recognized the underwear from this morning.Gwen continued to do her impromptu striptease removing her bra.Croutching in front of me she gave me a splendid view of her cunt lips as they pressed against the straining silky gusset of her panties which also clearly showed signs of dampness.Slowly she stood and slid the panties off before throwing them in my direction.By now my cock was straining in my pants.Gwen stood over me with her hands on her hips,saying that I had seen all that she had to offer how about me showing her mine.Leading me through to the lounge she sat on the sofa while I eagerly removed my clothes.Complimenting me on the size of my erection she said she hoped I knew how to use it.Reclining on the sofa she opened her thighs and pleaded for me to come and fuck her.Slipping between her thighs she guided my cock into her sopping cunt.After a frantic fuck I came filling her cunt which triggered her own orgasm. I asked Gwen why she had done this,she said that after this mornings chat she had become determined to have some sex before the day was out,adding she had chosen me as she knew I wouldn`t dare tell Trevor so it would be our little secret. I went to get up to get dressed when Gwen asked where I was going as she hadn`t finished yet,she wanted me to screw her again only this time more slowly and with passion.Throwing some cushions onto the floor we moved in front of the fire.Gwen moved down and took my flacid cock into her mouth sucking me to full attention once again.Laying side by side we explored each other in a sumptuous 69er.When the mood was right I rolled Gwen onto her back and proceeded to kiss her neck and breasts.She placed a cushion uner her hips and urged me to enter her.By the light of a single table lamp we made love.Gwen orgasmed time and time again before she begged me to come so she could feel my hot juices in her.Build up speed I came on cue Gwen came again.Thanking me we cuddled and kissed further as we recovered.It was just after 22:00 as we lay exhausted on the lounge floor,when her sister phoned.As she spoke,I slowly fingered her slit and played with her nipples making her moan with pleasure.It was obvious her sister was wanting to know what was going on.Gwen began to explain to her sister what she had been doing,going in great detail how she had orgasmed while making love in several positions.Giggling I heard her tell her sister that she would only be willing to share me if she kept it a family secret. As I finally dressed to leave,Gwen asked if I had fixed the machine,the reason I had come over for,but had to tell her I hadn`t.Gwen smiled and said good as she would have to come over to my place again,and as I had been such a good lover she would ask her sister to join us. The next day Gwen as good as her word turned up with her sister Val who before I had time to close the door began to remove her clothes as she ran upstairs looking for the bedroom.For the rest of the day the two sisters went about wearing me out before they both left well satisfied themselves. Trevor is due back next week so Gwen and Val have arranged for one last liaison between us three at the weekend.Val has also promised to call round for some one on ones while Gwen and Trevor go away for a short holiday so i don`t feel left out.