All persons engaged in sexual activity in this story, are over 18 years of age.
This story took place in the 1970s in the United Kingdom when the 'World Wide Web' or Internet as it is known today, was barely an infant and not available to private individuals. As for mobile phones, they were only at an experimental stage. This meant that knowledge of sex was gleaned mostly by chats with 'experienced' friends or looking at adult magazines aka Playboy, Penthouse, Hustler and so on.
Boys and girls were nowhere near as mature or knowledgeable about sex at age 18 compared to many of today's 14 or 15 year olds, thanks mainly to the multitude of internet 'information' that can now be accessed by anyone that can type 'sex' into a search engine.
All of this is to set the scene for you, to make you aware that in the 1970s, unlike the present, many boys and girls at age 18 were considerably naΓ―ve when it came to real sexual encounters.
Obviously, if you have read the previous chapters you will be more in tune with the characters.
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Wednesday afternoon, with Sue in my shed, had been the furthest either of us had ever gone sexually with anyone. There was no doubt that we had both enjoyed it, but I think we were both reflecting on what we had done together and if it was wise to do more. We both knew the risk we were taking and the possibility of being caught by our parents, or even suspected of being sexually intimate, would have disastrous consequences. Although we hadn't discussed or agreed anything, we both tried to act indifferently towards one another for the next few days, trying to just 'act normal', whatever that was.
It must have worked, because our usually astute mom, didn't pick up any bad vibes between us and dad was his normal 'oblivious to most things' self.
Since Wednesday, I hadn't really seen Sue much. I was on half-term break from college, she worked all day, and was at work before I even surfaced in the mornings. In the evening, we ate our meal as a family, then I might watch some TV with our parents or go down to my shed to tinker with something or other, while Sue often went to her room to play some of her records.
The thing I was tinkering with most often in my shed, while keeping a good lookout for anyone in the garden, was my cock. I spent considerable time with the panties that Sue had left with me on Wednesday, wrapped round my cock, while I read some of the growing collection of 'men's magazines' that I kept in the two drawers, that I had fitted with false bottoms. I made sure that I didn't buy the magazines from the local newsagent that my dad uses, but from one near my college. However, having been away from there for two weeks, I had visited a couple of other shops that I hadn't been to before, and found one magazine that had more explicit photos than the rest. This one showed men licking girl's pussies and the girls sucking men's cocks, either before they had actual sex or sometimes instead of it. Some of the stories and letters pages also had some detailed descriptions of these things, that fuelled my imagination and wanking sessions. I had heard that both of these can be extremely exciting, but had not tried either, so it was left to my imagination as to how it might feel to be sucked, and how it would taste and feel to do it to a girl.
On Sunday in the late morning, Sue went with some of her friends to play tennis on the courts at the local park. I was therefore the only one there around lunchtime when Mom came down to my shed to say that she and Dad were off to visit grandma again, who hadn't been well during the week. Fortunately, instead of my magazines, I was actually reading a college textbook to refresh my memory on a couple of projects, in preparation for my return to college the following day, which she was pleased to see. Grandma lived about forty minutes away, so they were leaving early, but like last week, had left me and Sue some sandwiches for lunch and would cook in the evening. We said our goodbyes, and they left me in peace.
I suppose it was just over half an hour later that I heard footsteps coming down to the shed. As I said, I was reading a textbook, so I hadn't been checking to see if anyone was coming down, as I wasn't doing anything that I didn't want anyone to see.
I didn't get a chance to look out of the window to see who it was, because suddenly the door was pushed open - I hadn't bothered to put the bolt on - and Sue came straight in.
"Down here again then?" she said.
"I think that's fairly obvious," I replied, not even looking round at her.
"You almost live down here, if you had a bed here too, we could rent out your bedroom and make some money, couldn't we?"
"Ha, ha, very funny,"
"They've gone then?"
"Who?" I asked.
"Mom and Dad of course, goodness, keep up Ben."
"Oh, yea, they left about half hour or so ago," I said, now that I knew what she was talking about.
She walked further into the shed so that she was standing in front of me.
My eyes opened wide when I saw that she was wearing the full tennis kit. White short-sleeved top, white, tennis skirt, that I couldn't help noticing was very short, white ankle socks and tennis pumps. Her hair was pulled tightly back in a short ponytail. The exercise she had been doing had given her a rosy glow to her cheeks, and her tanned limbs contrasted beautifully with her all-white outfit.
My cock started to harden at the sight. "Wow," I said, without thinking, "you look good today."
"Well thanks bro, have you had a personality transplant or something?"
"What do you mean?"
"Well you don't normally say things like that?"
"I just mean that you look healthy and fresh?" I said. awkwardly.
"Hmm, well, healthy maybe, but 'fresh', maybe not, after all that running about," she said, sniffing her clothes. "It looks like you are actually reading something useful today," she smirked.
"I think reading all sorts of things are 'useful', don't you?" I grinned.
She started to blush and moved to look out of the window, giving me a great view from my lower vantage point of her pert bottom, only hidden by an inch or so of skirt. "Mmm, I suppose," she admitted.
Seeing her long bare legs and almost being able to see the globes of her bottom took my cock to near full erection. "Did you like the reading material we shared?"
"It was ...interesting." she replied, still not looking at me.
"Did you...like what we did last time you were in here," I asked, wondering why she was hanging around in here today.
"Did you?"
"Yea, of course. You didn't answer though."
"Yeah, I did like it," she finally admitted quietly, as she picked at a wood splinter on the rough window frame. "But,..I was a bit scared of how far we went, weren't you?"
I thought for a moment, trying to say the right thing that would assure her I wouldn't do anything she didn't want, but also wouldn't stop us doing things together.
"I was just a bit scared of how strong our feelings were, but it was sexy though wasn't it? Him touching you there like that, and it wasn't as if I would do anything without you wanting it, you must know that?" I said.
"I suppose I do deep down, it's just that...those feelings sort of creep up on you and it's like you can't stop, do you know what I mean?"
"Yea, I do see, I feel it too, like it gets more intense each time we do something different."
"Exactly," she said, "and I worry that Mom or Dad might catch us or work out that we're doing something."
"They shouldn't if we are careful, but even just talking to you about it makes me feel a bit...like randy, does it you?" I asked, hoping she would feel the same.
She concentrated on picking at the splinter, "It does a bit," she mumbled.
"Are you like,.. in the mood to do anything?" I asked, gently rubbing my hard cock through my shorts, behind my book where she couldn't see.
"I am sorta, but I dunno, I am all sweaty from playing tennis, I think I really need a shower."
"I don't mind I said, if you really feel like it," I cajoled, seeing the opportunity slipping away.
I could just see her chewing her bottom lip.
"No, I feel too dirty, but...what about if you join me?" she almost whispered.
"Join you?" I said, stupidly, "in what?"
"You know, in the shower." She was blushing heavily now and had almost picked a large bit of wood from the window frame.
"You mean both of us in the shower, together?"
"Yeah,...would you want to?"
"I would, but what about them, they might come back early or something, we wouldn't be able to hear them."
"Yeah , that's true."
"It would be very sexy though wouldn't it, wash each other's back, and stuff," I said, feeling excited now at the prospect of being totally naked together with my sister.