Note: This story was dynamically reformatted for online reading convenience. This story goes back to when I was in my early twenties, and I finally met a girl who would indulge in all of my favourite fantasies and more, a girl who seemed completely in tune with my own tastes, and who unashamedly shared all of her wildest fantasies with me. Heather liked spanking, and she liked it a lot. In the first few months of dating it was reasonably tame, but as time went on and our inhibitions dropped away we would engage in all sorts of spanking games and role-play. She would be a naughty schoolgirl and me a headmaster, or a girl I was babysitting for who wouldn't go to bed and needed to be spanked, or even a naughty daughter on some occasions. I could write pages on the games we would play but that's for another time. I remember it as a time of sexual bliss, but there was one week in particular week that will always stay with me, and I find myself often returning to it in my mind. As far as I can remember, the start of things happened when we were lying in bed one night and she turned to me and asked me if I had ever seen a real spanking. I replied that I had just given her one, but she then said 'No, I mean a REAL spanking. A spanking of a girl getting punished for something properly naughty, not just a game' I replied that I hadn't, and she asked me if I would like to. 'Erm, well, yes, I suppose I would, wouldn't you?' She had a thoughtful look in her face as she replied 'yes, I suppose I would'. The conversation moved on, and I thought nothing of it until the next week when I went to visit her at her parent's house. Heather still lived with her parents, although they had gone away for a week leaving just her and her sister Sarah alone in the house. Sarah was considerably younger than Heather, and it transpired quickly that Heather had been given responsibility for looking after the house and to some extent for looking after Sarah. As we went into the kitchen it became apparent that things had quickly gone down hill since Heather's parents had left, as the kitchen was a complete mess with dirty pots and pans and crockery stacked up untidily next to the sink. 'Oh for fucks sake!' cried Heather 'Sarah! get down here now!' she yelled at the top of her lungs. I heard the sound of her younger sister padding down the stairs before she entered the kitchen. 'What! Jesus can't you give me a break, I was busy!' Sarah was a pretty girl of medium build with pale slightly freckly skin and long brown hair, she was wearing her school uniform and looked very much like a younger version of Heather. 'What's all of this mess? I told you to clear it up before I came back didn't I?' Sarah, full of teenage outrage started yelling back 'I'll clean it up later, you're not Mom you know' Heather, her temper rising fast replied in a surprisingly controlled tone 'No, I'm not Mom, but I do have authority over you, or have you forgotten that little discussion?'. Sarah blushed and quickly backing down said 'okay, okay' before starting on the washing up. This was a surprise to me, as from her tone I was expecting all out war and not the sudden surrender I had just witnessed. We wandered into the lounge and I asked Heather what she had meant, but she just looked at me and said mysteriously 'Oh, you'll see soon enough'. Almost on cue a loud crash came from the Kitchen followed by the exclamation 'Oh Shit!'. We quickly went into the kitchen to see what had happened and saw what appeared to be all of the dirty plates smashed to pieces on the floor. 'Shit, couldn't you be more careful!' shouted Heather. 'It wasn't my fault! They just slipped, and if you hadn't made me wash them up in the first place none of this would have happened! Mom's going to go ape shit when she finds out!' 'Yes she will' replied Heather in a stern voice. 'And I think I know exactly what she would have done, and exactly what I should do while I am in charge and acting in her place'. Sarah seemed to visibly pale 'You can't be serious, you've got to be fucking kidding!' she replied with a slight tremble in her voice. By now I was starting to get pretty excited, it couldn't be possible, but could this really be heading the way it looked? In all my time with Heather I had never seen her take on such a strict persona, whenever we had played our games she was always the nervous schoolgirl who would reluctantly do what she was told, however this was different entirely. I knew from many conversations with her that her Mother had spanked her when she was younger, and in fact had extracted every detail from her about her spankings, picturing the events in my minds eye as she elaborately described the events of her younger years. I also knew that Heather wholeheartedly enjoyed telling me of how her Mother pulled her knickers down for her punishments, and it suddenly dawned on me as I watched her that this stern strict older sister act was based on how her Mother had talked to her when a spanking was due. I was so excited I thought I would faint, just how far would she take this? 'Come into the lounge with me' Heather said in a no-nonsense voice. 'Heather, please, don't do this!' 'Come into the lounge NOW' she stated again 'and Mathew, you can come to'. Sarah seemed on the verge of panic, 'Please Heather, don't do this now, wait till Mathew goes home!' 'NOW' was all Heather said as she walked into the lounge with both Sarah and me following. My heart was beating fast wondering what would happen next. Heather told me to sit down on one end of the couch, then sat down on the other end. 'Stand here in front of me' she told her sister, who on shaky legs did as she was told. 'Now, tell Mathew what Mom does to you when you are naughty' 'Please Heather, PLEASE NO! Don't make me do this!' she replied on the verge of panic. 'Tell Mathew NOW or I phone Mom who will ground you for a month as well as punish you!' In a trembling voice Sarah started talking 'When I'm naughty, Mom, Mom sp sp spanks me' she stammered out. 'That's right' said Heather 'Mommy pulls naughty Sarah's knickers down and smacks her bare bottom'. I could see that Heather was clearly getting off on all of this, and it seemed exactly like the sort of role play that we had enacted many times, however this time it was real! 'Right' said Heather in her no-nonsense voice 'pull up your skirt'. For a couple of seconds there was silence and nothing happened, Sarah's face was bright red with embarrassment 'Please, I'll do anything, please, not in front of Matt' 'PULL UP YOUR SKIRT' repeated Heather her voice getting louder with each word. Sarah then slowly hitched her skirt higher, up past the middle of her thighs, up until just a fraction of her white cotton panties were visible. I was practically opposite her and felt compelled to stare as her humiliation unfolded. 'Higher' said Heather in her strict maternal voice. 'Please! Mathew is LOOKING AT ME!' Sarah half screeched. Well I couldn't deny it, who wouldn't look? 'That's all part of the punishment, and maybe you'll think about that next time you don't do what you're told, now pull your skirt up all the way or I swear I will cane you!'. That seemed to do the trick, and Sarah quickly completed the job and pulled her skirt all of the way up to her waist. She closed her eyes and just stood there looking faintly ridiculous with her long school socks up to her knees followed by an expanse of smooth white thigh leading up to her pure white panties. My erection was straining at my jeans, and with her sister's eyes closed Heather quickly reached across, grabbed the bulge through my jeans and gave it a squeeze. This was almost too much and I almost lost control, but somehow managed to keep from cuming there and then. This was just too weird! 'Right, bend over my knee' By now Sarah was almost on the verge of tears, and wanting to get the humiliation over with as quickly as possible draped herself over her big sister's knees so that her legs and backside were directly facing me. Heather then began lecturing her sister and spanking her in exactly the same manner as she had described her Mother spanking her. 'You are a very VERY naughty girl' she scolded SPANK! SPANK! SPANK! SPANK! 'And naughty girls need a good smacked bottom' SPANK! SPANK! SPANK! The loud crack of each smack and the quick reddening of her Sister's bottom were testament to the force in the blows, and I have to admit that I was genuinely surprised at the force of the spanking. Sarah was now openly crying 'Please! Please, that's enough!' The site of Sarah's plump buttocks bouncing under her Sister's hand only feet away from me was driving me crazy, but things were about to get even better. 'Enough? I DON'T THINK SO' and with that Heather grasped her Sisters knickers in both hands and quickly yanked them all the way down to her knees. The sight of Sarah's pussy lips suddenly bouncing into view will be with me for the rest of my days, I thought I had gone to heaven. Sarah cried out in shocked surprise 'NO! NO! Not like this in front of Mathew! NO!' Heather held her in place as she tried to writhe free but continued to rain down smack after smack 'You WILL' SPANK! SPANK! SPANK! 'Have your bare bottom spanked in front of Mathew!' SPANK! SPANK! SPANK! 'And you will respect me' SPANK! SPANK! SPANK! Sarah's twisting and turning meant that her legs were opening and closing give me a perfect view of her lightly covered pussy, and it was all I could do to not reach out and touch it. Finally it was over and Heather let her sister get up. Her sister had pulled her skirt right up for her spanking, and being fairly short and tight it didn't drop down immediately as she slowly raised herself, but remained bunched up around her waist. Incredible, it appeared that she was so distraught that she hadn't quite noticed this as she was getting up. At the point she was almost upright I looked at her tear streaked face and our eyes momentarily locked, her eyes then flicked to the bulge in my jeans then widened in shock. I shouldn't have done it, but at that perfectly wrong moment I couldn't help my eyes flicking down to view her sparsely covered slit in all it's exposed glory. In a strained voice she cried in humiliation 'Oh my GOD!' before quickly covering her nakedness and running upstairs. As soon as she was gone from the lounge Heather practically jumped on me, kissing me and rubbing my cock. 'So I take it you liked that?' I didn't have much time to answer as she dragged and mr upstairs and we fucked in a frenzy of released tension. To be continued ...