Back in the late seventies and early eighties I was a post graduate archeology student studying for my master's degree in the UK. I had grants and everything but my girlfriend, Nicky, had a good job and that made life easy. In those days our relationship was what was called open. We loved each other but didn't put too much emphasis on fidelity. I'd sat on the sofa and watched her get screwed by other guys. I'd joined in and even fondled their balls or licked her clit while she was being ridden. Nicky knew that I would find some undergrad to empty my balls into during the summer field trips and we were both happy with that situation. 

As part of my studies I was making a survey of a site we would be digging during the summer. I had an old class mate, Alan, living close by with his wife Sue, so I stayed with them. Nicky and I had grown up with them and had stayed at their flats and bed-sits quite often. We had all seen each other naked, fucked in front of each other and even swapped partners a few of times. I'd also fucked Sue without Alan knowing.

He had decided not to study further and had a job as a trainee store manager for a large chain. They had the flat above one of the stores and he earned enough money to allow Sue to be a lady of leisure. The only drawback was that one room of the flat was used as an office for his area manager Donald.

I spent most of the day sketching and measuring lumps and bumps in a couple of fields an hour’s drive from Alan and Sue's place. The sun was warm and the air smelt sweet with the fresh green spring morning, but by early afternoon the black clouds had rolled in and the sky was lit up by an electrical storm.

I had made it back to the car before the heavens opened and emptied rain, hail and more rain over the countryside. I had done enough for the day and could spend the afternoon writing my notes up. I had been given a key to the flat and quietly I opened the front door of the flat; hearing sounds of grunts and moans I expected Alan to be home, but no. The door to the office was open and Donald had his bare arse to me; his trousers and pants were around his ankles and he was pumping away at an equally bare arse, Sue's. 

I've fucked her; I know what noise she makes with a cock being slammed into her; a long low moan with open mouth, or short breaths in time to her lover's thrusts. Quietly I went back out into the rain, closing the door very gently, and sought refuge in the café over the road. I could watch the flat from there and try to work, but the thought of Sue getting screwed over Donald's desk kept coming back to me.

After an hour and four coffees, the office light blinked off, then Donald's car turned into the main street and was away. I gave it another ten minutes and went back to the flat.

Sue sat on the sofa leaning to her left with her arm on the armrest; the hem of her dress had ridden up giving me a peek of her knickers.

“Hi, Sue,” I breezed in and sat beside her. She leant across smiling and gave me a peck on the cheek then leant back across the armrest again.

“You look like the cat that got the cream,” I said.

“Do I?” She smiled.

“Yes, and I saw Donald pumping it into you earlier.” Sue froze.

“I came back about two o'clock and there you were bent over his desk with him, his trousers around his ankles and dick buried in your fanny.”

“I'm sorry, Rick, I thought I had locked the door. Look he doesn't mean anything to me, I still love Alan, it’s just that...”

I stopped her mid flight. “Calm down, Sue, I'm not upset. I'm not Snow White. All you have done is make me feel is horny as hell.”

I reached down and traced the outline of her fanny lips through her knickers. I knew this pair, they matched her bra; a soft almost see-through material was soaked with the mixed fluids from her earlier love making.

“We've made out so I know what it feels like to pump spunk into you and watch your face as it happens. It's a real turn-on the way you enjoy letting it run into your knickers. I hate it when girls run to the toilet and stuff a wad of toilet paper between their legs to mop up any cum.” I pushed her panties up between her open labia, it felt warm, damp and sticky. I didn't care that it was somebody else's spunk, I just wanted to fuck her as well. 

I leant across and softly kissed her neck and pulled her knickers away from her fanny; my fingers explored her labia and the hot sticky hole that lay between them. Her breathing got heavier then I turned her head to meet my lips. Sue's mouth was open and willing, our tongue's danced in each other's mouths and I knew she would not resist my advances.

Sue swallowed. “What are you going to do?”

I pushed her gently back across the sofa arm; she must have heard the zip as my fly came down but didn't move. I pulled my jeans and Y fronts down to my knees; my stiff cock sprung free and I guided it to her entrance. She gasped as I slid it along her crack, but still didn't pull away. I pushed up into that warm welcoming hole, I felt its heat and buried my cock as deep as it would go.

Nicky told me Alan's dick was about seven inches long and thicker than mine, but that still gave me an inch and a half advantage over him. We both sighed as the end of my cock met a wall of flesh and could go no further. 

Reaching around her I opened the two top buttons of her dress and slid my hand in to cup her left breast. The same gossamer thin material that molded around her labia also cradled Sue's soft full breasts; they hung in her bra cup, the nipples were dark and prominent, just right for suckling on.

She was taller than Nicky and better covered than girls I normally made a play for, but she had a body that craved to be pregnant; I could always tell when she was at her most fertile, she wreaked pheromones and my skin itched to touch her; she was at this point now.

She leant further across the sofa's armrest to give me a longer stroke and I took full advantage it. Her mouth was open as she panted, intoxicated by my hard flesh invading her. I pulled her head to face mine and I locked my lips around that open mouth. We shared the same breath for a while, passing it backwards and forwards into each other's lungs until we were giddy with lust and the lack of oxygen. 

I pulled out and stood up, my trousers around my ankles and my cock standing to attention. Sue looked at me expectantly, her eyes questioning why. Taking her hands I helped her stand. Kneeling, I undid the few buttons of her dress that held it together, and brushing the garment to the sides I pulled down her knickers, sodden with Don's cum and the juices she was oozing to lubricate our own union.

I gently lowered her to the floor; as she lay before me, her dress fell to her sides. Erect nipples tried to pierce their gossamer prison, legs open and her wanton pussy waiting to be filled with fertile sperm. My senses screamed at me to fulfill her biological need. 

I quickly stripped and got back between her legs. Sue reached out and guided my erection to her open pussy; pulling both bra cups down I freed her nipples, there now to arouse my passion. The perspiration from our love making had chilled on Sue's body and her skin felt cool against mine, but her pussy was still like a hot glove around my cock; my balls boiling with cum waiting to be spewed into her.

Sue's pussy was accustomed to Alan's extra girth and I wanted to be clamped by a tight hole. I spread my legs over hers, keeping them closed and her thighs squeezed tight against the base of my shaft. I was focused on one thing only, shooting my sperm as deep into her womb as I could. I started to fuck Sue as hard as I could. This wasn’t for her enjoyment it was my body telling me to do it. I didn't last long in that hot cunt. I felt my cum surging up my shaft; I gripped her ass I pulled our bodies together. Squirt after squirt pumped into her, Sue laying back and moaning as I filled her. 

I slid across and lay beside her. Sue rolled towards me and put her head on my shoulder then caressed my softening cock as it leaked cum onto my thigh. She rubbed her finger tip into the little pool feeling its thickness; Nicky said that Alan's spunk was always watery. 

“I love the way you cuddle me after sex. Don pulls up his trousers and says he must carry on working and Alan just falls asleep.” Sue moved closer and kissed my chest.

“We shouldn't have unprotected sex,” she said after a moment. “Not while Alan and I are trying for a baby. Don is okay, he has had a vasectomy, but you could make things complicated.” 

“Sorry, honey, you turn me on so much sometimes that animal instinct takes over.”

Sue stirred. “We mustn't be found like this.” She got up and walked out of the room.

I quickly dressed and walked up the hall, the bathroom door was ajar; Sue stood naked, one foot up on the side of the bath as she inserted a tampon. “Sorry Rick, but you left so much cum I have to clean up somehow.” 

I smiled. “Best I go back to my site of a couple of hours, I don't want to have that ‘I've just fucked your wife’ look when Alan gets home.”

Sue smiled and I went out again into a warm spring afternoon.

I got back a couple of hours later; I hadn't done much more work, I was suffering from PISS, post-illicit-shag-syndrome; head in the clouds and smiling like an idiot.

As it was my last night with them, I had said I'd cook that evening, a typical student chili; rice, onion, canned baked beans, minced meat and chili powder to give it more taste than the beer. Alan was fuming about some customer that had spent hours asking him questions about different products. Then when he thought he would close on the sale the guy said now he knew what he wanted he would get it mail order because it would be cheaper. The more upset Alan became the more Sue and I giggled. That didn't help Alan's mood but at least it covered our PISS look. 

We all went to bed about eleven pm. I heard Sue and Alan talking, but too muffled to know what they were saying, and then giggles; then Sue's grunts as Alan's cock was sliding in and out of the same hole I'd enjoyed a few hours before. Three different cocks in one day, Sue, you really are on heat at the moment. 

I was up early and showered. Alan was only a few minutes behind me. As I left I asked him to say goodbye to Sue for me and told him I would get over to see them a couple of times during the summer field work. Then I threw my stuff in the car and left. I didn't go too far and parked where I could watch his route to work. It was no more than half an hour before he passed, which surprised me, but then I headed back towards his wife's warm body. 

“What have you forgotten now?” Sue called as I let myself in.

“To say goodbye?” I quipped as I opened their bedroom door. Sue lay naked on her front, a pillow under her tummy pushing her arse in the air.

"Well, now that is a welcome.” I smiled.

“No, Rick, you can't. Alan and I made love before he left and I am trying to keep his sperm in me so that I can get pregnant. I don't want your sperm or any spermicidal on a condom thank you.” Sue was emphatic. 

I sat on the bed and ran my finger between her buttocks. I knew she enjoyed anal sex and that Alan thought it was disgusting; she thought the same way about blow jobs which was why Nicky had always tended to Alan's need if we swapped together.

“Seeing you like this I can think of something else.” I leant over and started to rim her.

"Stop, you bastard." She groaned.

I pushed my tongue into her hole and reached for the butter pat I'd taken from the café the day before. The butter was warm and I smeared half of it onto her ring, pushing it inside with my finger. Sue moaned as I slid all of my index finger into her; my other hand was busy with my belt and freeing my cock. The rest of the butter went over by helmet and I shuffled between her legs, leant forward and pushed my cock up into her arse.

We didn't move for a moment, letting her become accustomed to my intrusion while I just enjoyed the tightness. I don't know who taught her about anal sex, there was a rumor when we there about sixteen that it had been her mother's boyfriend, but whoever it was he had taught her well.

I kissed her neck and shoulders; my full weight was on her back now.

“Are you going to be a good girl and cum for me?” I asked. She froze for a second as if remembering something from long ago.

“Yes,” she said meekly.

“Good because my spunk is going to squirt deep into this warm inviting arse of yours.” Sue moaned though another orgasm.

I didn't want to hurt her with a long session of anal sex or get caught by Donald, so I pulled out until just my bell end was in her and stroked my shaft until I was on the point of orgasm, then plunged in again; my timing was perfect and my load shot into Sue's bowels to be greeted by her muscles contracting with another orgasm. 

I pulled out slowly and watched the gaping hole slowly close with my spunk inside. Reaching across to the bedside table I took a tissue from the box, cleaned the now tight hole, then kissed it again. It still tasted of butter, cum and Sue's sweat and juices. 

“You're a dirty bugger.” Sue smiled at me. 

“And you're a good girl who has got a fanny full of hubby's spunk to make her pregnant, and an arse full of her lover's spunk to make her feel horny all day,” I answered. 

I got up to leave for the second time. “Now you keep that arse of yours tight shut until the summer when I see you again.”

“I'll try.” She smiled.

I knew she wouldn't; I didn't think that it was only Don and I who were fucking her and she did love spunk in her, especially her arse.

“Rick,” she said softly, “are you going to say anything to Nicky about us making love? I know you two are more open about it and if I speak to Nicky on the phone…” her voice hung for a moment.

I smiled. Sue didn't like keeping secrets and knowing that I could tell her friend and my girlfriend eased things for her.

 “I'll tell her I ravaged your beautiful arse this morning.” 

“Okay, thanks.” She relaxed and settled into the pillow again. I kissed her tenderly on the lips and then on the reddened hole between her buttocks.

“Stop that or I will demand you stretch me open again.” Sue giggled.

 I drove to my field site feeling that PISS again. Roll on summer.

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Author's note: A lot of this story is autobiographical, names and reasons for being there are changed, but the girl was real and so were the things she did and liked.