"Gary." my mother's voice drifted up the stairs.

"Coming mum." I yelled back after groaning to myself.

Putting down my latest copy of Playboy and stuffing my erect tool back into my trousers, I got off the bed and headed for the bedroom door wondering what mum wanted now. A few minutes later I found out what it was.

"Gary," mum said as I entered the kitchen "your father and I have to go away for a week, Sandra will take care of you while we are away and I want no arguments from you."

Inwardly I groaned at the thought of having my sister in charge of me for a week, she was a seventeen year old pain in the backside, pretty, but a pain. Reluctantly I agreed to behave myself before it dawned on me that I would be on holiday and, horror of horrors, so would she, this had to be the worst day of all my fifteen years. Feeling glum I returned to my bedroom and flopped on my bed, even the sight of my copy of Playboy did nothing to cheer me up.

Early the next morning my parents left for wherever they were off to leaving me to the tender mercies of my older sister. Barely had my parents left when Sandra was laying down the law.

"Right Gary," she said "while mum and dad are away you are going to give me a hand around the house. You can start by tidying that pig sty you call a room."

"Aw, come on Sandra," I protested, "it's not that bad."

"I knew your promise was no good." she smirked.

She knew as well as I did that I had never broken a promise, her comment was totally uncalled for and I her told so.

"One day I'll get my own back." I finished.

Storming up to my room I set to putting away the few things that were laying around then flopped on my bed and sulked. Although I loved my sister she was a bitch at times, usually when she was in charge, which was too often for my liking. Glancing around my room I spotted the copy of Playboy lurking in a corner, God knows why, but the thought popped into my head of what my sister would look like naked. I was surprised at myself for having this thought, even more so as I realised that I was getting turned on by it!

"Gary, stop wanking and get down here." Sandra's voice drifted up the stairs to me.

Angered by her words I went downstairs, she wasn't in the living room so I went into the kitchen.

"Come on," she grinned, "dinner's on the table."

The wind was taken from my sails at her announcement, her shout had obviously been a wind up and I had fallen for it, this only increased my determination to get my own back on my sister. Nevertheless, dinner looked and smelt good and my thoughts of revenge could wait until after dinner.

Over the next two days my sister made my life a misery, winding me up then defusing me until I was ready to blow my top. Yet even then I found myself becoming increasingly excited by the idea of my sister in the nude, I was shocked to even find myself fantasising about my sister while I was wanking. Then, quite by accident, I got the chance to get my own back on my sister and satisfy my erotic curiosity, a chance I didn't hesitate in taking.

It was early on the third day of my parent's absence, I had woken from a wet dream and headed for the bathroom to clean myself up, as I passed my sister's room I heard strange sounds coming from inside. Curious I peeked through the keyhole and there was Sandra, naked and wanking for all she was worth, grinning I watched her for a few minutes before I had an idea. Quickly and quietly I dashed back to my room and grabbed my camera, racing back to my sister's door I put the lens to the keyhole and looked through the viewfinder. Joy oh joy, through the SLR lens I could see my sister still busy with her pleasure, her body revealed in all its naked glory, eagerly I began pressing the shutter release, I had twenty unused pictures and I snapped every single one of them. The last picture I took was a dilly, it was of Sandra climaxing, her fingers buried deep in her pussy, her body arched as her pleasure had peaked, grinning like a Cheshire cat I took that shot and returned to my room with my tool leading the way. Safe in my room I rewound the film, unloaded the camera and put the film safely into its container, hurriedly I dressed, put the precious film in my pocket and went downstairs to make myself some breakfast.

Sandra joined me in the kitchen about ten minutes later, she still looked flushed from her pleasure play, and she was also puzzled by me greeting her merrily.

"Morning sis." I grinned, "Sleep well?"

"Yes thank you." She responded with a raise of an eyebrow "You're in a good mood this morning."

"I am aren't I." I grinned, "By the way, I've got to go out this morning."

"Oh, is that so." she said sarcastically "And where would you be going young man?"

"I've got some films I want developed," I grinned, "I'm only going to the shopping mall."

Sandra knew the mall I was referring to, it was about two miles from the house and I usually went to the SpeediPrint shop there to get my pictures developed, what she didn't know was the reason I used that particular shop. It was because the technician there was a lazy bugger who never, but never checked the prints or negatives put out by the automatic machinery. She mucked about pretending to want to prevent me from going out, but eventually 'deigned' to give me permission to leave the house unaccompanied, I had known she would as there was no valid reason to stop me going. Feeling triumphant I left the house and made my way to the mall and the photo-shop, depositing my films I paid my fee and hung around for an hour at the end of which time I returned to the shop and picked up my pictures.

I could barely wait until I was clear of the crowds to open the envelope and check my pictures, the machine had done a perfect job, four pictures of wildlife followed by twenty pictures of Sandra having a wild time, all in wonderful Kodak colour. Almost hugging myself I rushed home, avoiding my sister I went to my room and separated the negatives from the prints. Grinning I put the negatives in the one hiding place I had that I knew Sandra hadn't found, under a loose board under my bed, then took the prints downstairs to the living room.

"Oh, so you're back." Sandra greeted me as I entered the room "Did you get your pretty pictures developed?"

"Oh yes," I grinned "and I think you'll like them."

"Really?" she said in a puzzled tone.

Grinning from ear to ear I handed her the prints, the top four were the pictures of wildlife I had taken, she looked at these and frowned in puzzlement as they were nothing out of the ordinary. Then she looked at the fifth photo, her eyes went wide as she stared at herself wanking, slowly she looked at the other pictures, her eyes widening wider with each one and her jaw dropping lower and lower.

"Gary!" she exclaimed.

"Yes Sandra?" I replied all innocence.

My sister looked at me with disbelieving eyes then back at the pictures, at first it looked as though she was going to rip them apart, but it dawned on her that these were only the prints, if she tore them to shreds I would still have the negatives.

"Where are the negatives?" she asked in a hushed voice.

"Safe." I grinned.

The joy I felt at her reaction filled me, at last I had managed to get my own back on my sister in a way that actually got to her, she wouldn't laugh this off so easily. Then my joy faded as Sandra burst into tears, I was confused, I had never intended to hurt her only embarrass her, the way she had embarrassed me. Dropping the pictures on the sofa my sister ran from the room, suddenly I didn't feel quite so smug about what I had done and it was only at that moment that it dawned on me that I had intruded on her very private pleasure. I felt like shit, there was only one thing I could do to make amends and that was to give her the negatives, a pity really as she looked smashing in the photographs. Picking up the prints I went up to my room and retrieved the negatives then made my way to Sandra's room.

"Sandra." I said softly as I knocked on her door.

"Go away!" she shouted in reply.

"Please let me in," I pleaded "just for a minute."

At first I thought she was going to ignore me, but then I heard the click of the lock and the door opened a crack. Sandra looked out at me, tears in her eyes.

"I, uh," I faltered, "I'm sorry sis. I never meant to upset you. Here."

I handed her the prints and the negatives and turned to go to my room as she took them, but she opened the door and indicated that I should enter. Following her in I sat on the edge of her bed and watched as she cut the negatives and the prints into tiny shreds then dumped them in her waste bin. She sat beside me, sniffed and dried her eyes then she gave me an almost shy smile, leant over and kissed me on the cheek.

"What was that for?" I asked.

"I don't know," she grinned "you don't deserve it after what you did. Why did you do it?"

"I wanted" I replied, "to get my own back."

"Why?" she asked in a puzzled tone "What for?"

"Come on Sandra," I said in amazement that she didn't realize how she had been acting "you've been a right pain over the last couple of days."

"Me?" she protested.

"You. You've bossed me around more than mum and dad ever do and in front of other people." I stated.

She looked thoughtful for a moment and it dawned on me that she might not have realised how strict she had been, perhaps she even thought she had been acting in the right way.

"Perhaps" she said shaking her head "you are right. I thought I was doing things the way mum and dad do."

She sighed which made her boobs rise and fall sharply, this of course reminded me of what those boobs had looked like naked and I grinned. My sister must have mistaken my grin for something else because she suddenly smiled at me and put her arm around my shoulder.

"I'll try to be less of a 'pain'." she grinned "Let's kiss and make up."

This was a ritual from our younger days, neither of us had invoked this for some time and I was surprised when she offered our old peace ritual.

"Okay." I grinned.

She leant over as I turned my head and our lips met in what should have been a brief peck, but as our lips met it was as though a spark passed between us and I felt suddenly aroused. Without thinking I threw my arms around my sister and pulled her close to me as I pressed my lips hard to hers, Sandra returned my kiss with a fervour that matched my own. A few moments later Sandra parted our lips, turned, lay on her back and put her head in my lap, she looked up at me with a smile on her lips and a gleam in her eyes. I don't know what she was feeling at that moment, but I was feeling hot and excited as I looked down at her. One of her hands rose to the back of my head, I felt her gently draw my head down towards her, once again our lips met, and once again I felt the spark pass between us. As our kiss drew out I felt something tugging at my chest, it took me a moment to realise that it was Sandra opening the buttons of my shirt, even as I had this realisation I felt her hand slide across my now bare chest. My heart pounded as her touch excited me, my tool twitched and grew, pressing against my pants, trousers and the back of my sister's head almost painfully, the action of her hand on my skin inspiring me to return her caress. Almost with a will of its own my hand fell to her chest, the swell of her tits under my hand exciting me even more as I daringly opened the buttons of her blouse and pushed the material aside. My hand trembled as I touched the warm flesh of her stomach then stroked my way upwards until once again I could feel the swell of her tits under my hand. For a moment I gently squeezed and rubbed her tits through her bra, then I pushed the bra up over her tits and put my hand onto her bare flesh, the feel of her hard nipple digging into the palm of my hand as I squeezed her pliant globe made me draw in a sharp breath of excitement. Taking the hard button between thumb and forefinger I teased it, Sandra responded to this with a moan deep in her throat, encouraged by this I played with her nipple.