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.
**********
Since my encounter with my sister Sue in 'my' shed on Sunday, when we had almost been caught by our mom, we had kept our distance. Mom was happy that we had made up whatever differences she had perceived we had, and hadn't suspected anything else, so all was back on a level footing. I was still on half-term holiday from college until next week, so I got to pick up a few chores while Mom and Dad and my sister were all out to work during the day.
I had found time in between chores to be in my shed several times, and as my sister hadn't yet retrieved her hastily hidden panties under the armchair, covered in my cum, I had made use of them a few times more. I know, that sounds really bad, and I don't think I had a panties fetish, but it was hard to resist when I thought of them having been in contact with my sister's wet vagina. On Monday when I pulled them out from underneath the armchair where they had laid hidden since Sunday afternoon, I couldn't help feeling the soft material and touching where they had pressed on her pussy along the gusset. The thought that they had been on her body, pulled up tight against her, and now were here in my hands, compelled me to wank again with the thought. During Monday and Tuesday, several times, I held them around my cock as I wanked and covered them in more of my cum.
Tuesday evening after we had eaten our evening meal as a family, Sue and I were asked to do the washing up, so we ended up next to one another at the kitchen sink. Our parents were only in the next room, so we initially just got on with the task. Sue was washing and I was drying, putting things away as we went.
I looked round to make sure we were alone, "Sue," I whispered, "do...emm...do we need to talk about Sunday?"
No reply.
I bumped her with my hip, "Come on Sue, you know what I mean, don't you?"
She looked around, "I know."
"Look," I whispered, drying another plate, "I need to know if... well...you are upset, mad, sorry it happened or what."
"I dunno Ben," she whispered back, "I am confused."
"Yeah, I know, I am a bit too."
"You are?"
"Well yea of course," I looked to make sure we were still alone, "it's not something I have done with anyone," I started to blush, "but didn't you feel really randy doing it?"
She looked into the soapy water, "I..emmm... guess I did."
"I know you are my sister, but ...umm.. you're also...like errr..."
"Like what Ben?"
"Well, you're a, girl."
She giggled quietly, "Yea, I know that Ben."
"That's not how I meant it," I was red in the face now, "I only know about...you know...those down there bits of you, from those magazines," I looked around nervously, "so touching you there, inside and everything, and making you feel good was just ...emm... just...only things I imagined and wondered about."
She was quiet for a moment and continued to wash saucepans and cutlery.
She looked over her shoulder then back down, "I know, but, no one has ever done that to me before either and it scared me that it was so intense." she said, almost too quietly for me to hear.
"But, did... umm . did you like it though?"
"Yes, of course, what do you think I am saying," she had that exasperated voice on again, like talking to an idiot. "But, can't you see, we shouldn't be doing it, and if ever anyone found out..." she left it unfinished.
Now it was my time to be silent, she had a point. The problem was that my cock was telling me it would be ok to do more, my real brain was saying she is right. But surely, my cock said, repeating what we had already done wouldn't be doing more, just the same, so no real extra guilt? It was very sexy and we both enjoyed it at the time, so...Perhaps? Oh damn, main brain into shutdown again.
The TV was on in the living room, so I didn't think we could be overheard, "I am not going to tell anyone Sue, are you?"
"Of course not."
"So...we could find out a bit more ...with each other, without anyone knowing?"
"I don't know Ben."
"Does it make you randy now, even thinking about it?" I whispered in her ear.
"God yes, but...I am not sure...if...you know."
My cock was fully hard by now, I turned slightly and pushed it against her hip.
"Ben! What are you doing," she hissed.
"I can't help it."
"I'm sure you can."
"It's thinking and talking about it..and.. what we did, makes feel me like this."
"Christ, Ben, you are going to get us into trouble," she said, a hint of panic in her voice.
"It's ok, they are busy watching TV."
I moved behind her and pressed myself up against her, my hard cock in-between those firm bottom cheeks.
"Ben!"
"Does that make you even more randy Sue?"
"Ben, not here, please, they'll see."
"You didn't answer me," I whispered, again into her ear.
"Yes, it does, of course it does, I can feel you there, but we've more or less finished the dishes now, so you better go to the bathroom or somewhere before they come in here," she said, more forcefully.
She was right again, standing next to my sister with a raging erection tenting my shorts might not go down too well with our parents.
I put the cloth I had been drying the dishes with back on the rail, and turned to go towards the stairs, "I have something of yours in the shed, and as it's Wednesday tomorrow, you might want to collect it in the afternoon when you get home from work ," I said.
Her brow crinkled as she processed that comment, then she remembered, and a barely concealed grin spread across her mouth, "Maybe."
**
On Wednesday, Mom and Dad were at work as usual, and just after 1pm, I had taken the sandwiches Mom had left me, down to my shed to eat them there. I had made it cosy and with the old armchair, workbench and various tools, it was like a sort of male haven. It smelt faintly of the creosote that coated the exterior wood as well as sawdust from the odd bit of sawing I had done. I had a small battery-powered, transistor radio, down there (for those of you that might remember, it was a 'Bush' with a big frequency dial on the right hand side - sorry I digress), which was tuned to Radio 1 and playing current pop tunes.
I was sitting in the armchair, finishing the last of the sandwiches, with the music at a fairly high volume, and reading some of the stories in a new magazine, so not paying much attention to anything else.
Knock, knock, on the door, "Ben, you in there?" my sister shouted.
I have to admit, I really didn't think she would come down to my shed after the last time she was here, and although I had teased her about what she had left behind, I still didn't think she would come.
I quickly slipped the new magazine under the armchair, and got up to let her in, putting my now empty plate on the workbench.
I slipped the bolt back and she pushed in almost straightaway.
She looked me up and down and then looked around.
"So...what are you doing?" she asked.
"Nuthin much, just had a sandwich and listening to music."
She looked disappointed at not catching me doing something else.
"Err, so... did you want something," I asked.
"You said you had something of mine?"
"Ahh yes, ummm. I kept them safe, in case...you know..."
"Great, can I have them then?"
"Yeah, sure, hold on."
I went to the drawers, deliberately shielding them from her view, pulled one open, lifted up the false bottom and extracted her panties she had left behind on Sunday.
"Here," I said, and offered them to her.
She took one look at them and said, "What the ...what have you been doing with them, they didn't look like this when I left them?"