Over the months of my relationship with my Master, I had grown to accept subservience, become accustomed to the need to consider first not my own opinions or desires, but those of another person. Now I was being asked to be decisive not only on my own part, but on behalf of another person, someone subservient to me. That required a fundamental shift in my behaviour, and I wasn't sure how I could manage it, not least given that at the same time my relationship with my Master was to be unchanged. I was being asked to perform as Master and slave at the same time.

And so I was in a state of confusion, which made my Master's latest diversion all the more satisfying.

I think he sensed the strain I was under, the strain our relationship was under, and he knew that we had strayed from our normal behaviour, which is why, I suppose, he deliberately chose my latest task in an attempt to try to return us to familiar territory.

It was a Sunday afternoon and we were having a picnic, stretched languidly beneath the shade of a magnificent monkey puzzle tree. Standing easily thirty feet high its beautiful, arced branches, like dreadlocks swaying rhythmically in the breeze, swooped in chaotic confusion down towards the ground where we sat, bunches of cones gathered at the ends of many of them like a child's impression of a hand, chunky and thrusting.

"Take your top off," he said, out of nowhere. Without a moment's thought I obeyed and slipped my tee shirt over my head, enjoying the lick of fresh air across my shoulders. He continued to chat away idly, as though nothing was amiss, all the time stroking my stomach and tickling my belly button. Giggling and squirming, I tried to resist.

We were in a relatively secluded area of the park, over the river from the main public area in a section used mostly by dog walkers and bird watchers. The latter were going to get a view of a most unusual breed if they happened past today, I thought: the lesser titted Harriet, perhaps. Consequently, I wasn't too worried about my mild exposure, and even when instructed to remove my trousers I felt only a minor twinge of concern. It was, after all, an unseasonably warm day and from a distance my sports bra and panties would easily pass for a bikini.

My Master stroked my inner and thigh and slyly pointed out the passing walkers, teasing me by suggesting they might walk straight past us, querying whether or not I fancied them. In general I did not, of course: they were mostly older people with closely reined, sullen looking dogs. But the thought of exposure, as my Master knew it would, caused minor ripples of excitement within me.

One person was different, however, a youngish woman with a mass of dark hair and a trim body. She was walking a small mongrel beast and had a languid, gentle walk, carefree and unconcerned. She was some distance away, but walking in our direction, and as soon as he saw her my Master began to tease me.

"Perhaps she'll come this way," he said. "Right past us. She'll see you, half dressed. What would she say? Scandalised, I should think. Can't see her face yet, but I bet she's attractive. I suppose you'd like her to see you, wouldn't you?" And so he went on, planting in my mind suggestions and notions, toying with me, gradually playing on my nervousness about being caught in public. All the while, the woman came closer, still, at this stage, oblivious of our presence.

"I think you probably ought to take that bra off now, don't you?" he said. I stared at him and swallowed nervously, then eyed the woman. She was still some distance away, and on the other side of the river. As long as she didn't cross at the small bridge downstream from us I would be okay, I calculated, and slid the bra over my head. Instantly, the wind on my breasts and nipples caused me to shiver, with trepidation rather than cold, and I was aware that I was becoming increasingly nervous. There was no way to talk myself out of this situation now. I tried to lie down, making myself as low to the ground as possible, hoping to conceal myself as best I could.

"Sit up," my Master said. I did so, resting on my outstretched hand, and watched the woman. Don't cross the bridge, I muttered under my breath. Don't cross the bridge.

She crossed the bridge.

It was now that I began to get really worried. She was on a path which would take her directly past us, not more than fifteen feet away, and there was no prospect that she would not see me. I stared at my Master imploringly, begging him with my eyes to be allowed to cover myself, but I knew there was no point. The woman had by now caught sight of us and seemed to be looking in our direction as she approached, but it was difficult to tell because we were in her natural line of sight in any case. Nearer and nearer she came, and finally I knew that she had definitely spotted us. And not only that, but I knew she had spotted me. And my nakedness.

She had been walking slowly all along, but now she had slowed almost to a standstill, and where before she had been looking around her carelessly, her eyes were now fixed ahead. Fixed on me.

"Say hello when she passes," my Master told me.

I waited in an agony of anticipation, my nipples taut and prominent, signposting my excitement. The woman was close now and I could see her face. At least I didn't recognise her, so that was a bonus. She was attractive enough, with well styled hair, wild and thick at the back but cut neatly around her face, drawing one's attention to her pretty features. I was more concerned, however, with my own features at present, those exposed ones which she was freely staring at as she passed by us.

"Hello," I said, my face crimson and my nipples stretched to their quarter inch limit. The woman smiled.