This all happened a few years ago - but it is still a very special memory
My wife's sister was living with us as she was having some problems. Hazel was a nice girl, but I had no sexual interest in her. My wife was the girl for me.
That being said, she came on holiday with us once, and when she sunbathed topless for the first time, I couldn't help but look at her small, pert breasts. She only did this the once on holiday, and I guessed she'd freaked out about her brother-in-law sneaking a peek...
Whilst living with us, she was very particular about her appearance, and would spend ages every day on her hair. At the time, the only decent mirror in the house was in our bedroom, so she would come in and get herself ready.
Most of the time I was at work, or downstairs, and never knew about this, and was suprised on one weekend when I was having a lazy morning in bed and she came in to say she was going out and would it be OK if she did her hair. I just said "yes" and left her to it.
She was in a T-shirt and a robe, with a towel round her head, and I was really not paying attention as her ritual began. The towel came off and then, to my great surprise, so did the robe.
There she was, bare-breasted and wet from her shower, completely ignoring me whilst she concentrated on her task.
And there was I, completely naked in bed with a pretty young thing topless in front of me. Tits jiggling as she dried her hair.
My cock rose and refused to calm down, and I could barely contain myself. I tried to cover the time with small talk to make her comfortable and to keep her in the room for as long as possible but eventually she finished and left - saying that she hoped she hadn't disturbed me too much!
This went on for a few weeks - always the same, and always with me needing a good wank when she'd left.
I decided, eventually, that I ought to return the compliment. She would bring me a coffee in the mornings during the week to help get me up for work, so my next step was easy.
One morning, I set my alarm early and waited until I heard her leave her room.