I snarled at my assailant and dodged him. My conflicting instincts told me to run away or fuck him. Reason won out for a while, so I clawed at his scarred face and ran for home. The Heat had come on unexpectedly, without its usual signs, otherwise I never would have gone out. I was within walking distance of home, and certainly within running distance. 

I sweat as I ran and the scent of my damnable pheromones poured out of me with it. I could smell three distinct men near me and I knew they could smell me. My juices pooled in my underwear before dribbling down my leg. My cunt urged me to slow down but I was still rational enough not to. 

If I was lucky, I’d be faster than the man closest to me. If my husband and I were both lucky, Jack would be home and ready to take me for himself. “Lucky” can be such a relative term, though. I didn’t feel lucky when I crashed to the ground only a few meters away from my door, but I felt very lucky as I rolled over to face a kilt hiked up over a magnificent cock. Of course, any cock is magnificent when The Heat affects how we perceive them. 

I smiled lewdly at the cock and the man behind it, but managed to call out for my husband even as I stripped my underwear out from under my skirt. “Jack! I’m outside! Jack! Hurry!” I genuinely hoped that my shouts would reach my husband to affect a rescue, but I shouted once more to taunt the man who was about to defile me. I sat up with my knees spread and willed my glistening labia to unfold, to reveal what was hidden beneath my copious curls. He pushed me onto my back and plunged his cock into my slick, welcoming cunt. I dug my nails into his back and wrapped my legs around his waist, as if he’d willingly quit before he could squirt out his seed. My hips met each of his savage thrusts to get his cum into me as fast as I could. 

There could have been a fight when the other two men approached, but they waited for their turn. I didn’t care. The distraction lifted the veil from my cravings long enough for me to cry out for Jack one last time. After that, I whimpered, “Jack, Jack, Jack” with each stab. The man tried to kiss me but I barked at him and snapped at his nose. I wasn’t interested in romance or intimacy – not with him. 

Then I heard him. “Kris! Push him off! You! Get away from my wife! I claim that woman as my wife and demand that you stop!” 

I was elated that Jack came for me, and yet I still encouraged the man to finish. “Ignore him! Be a fucking man and finish your fucking job!” 

Jack yanked on my hair on the back of my head, and pointed a gun at the man. Guns had been brought on the Ark just in case the passengers needed them on this new planet. The weapons were subsequently given to married men, supposedly only for this lawful purpose. “Don’t make me,” Jack warned. “You wouldn’t be the first, and I already have a hole in the ground for you.” 

Jack lied, but they didn’t know that. I felt the cock retreat from me and I screeched at him to put it back in. Jack tugged hard on the hair he had balled in his fist. “Get up, Kris, or I’ll drag you in!” 

I stood and redirected all my attentions to Jack, reaching under his kilt to buff his rigid rod. He hauled me by my wrist toward our house, and I almost fell as I looked back. I panicked when I saw my foregone suitor waste his ejaculate. Jack had to be rough with me to get me inside, but that was okay because I was rough with him to get him inside. 

I dropped my skirt and stood on tiptoes to impale myself where we stood, but knocked him over instead. I joined him on the floor, shoved my knees under his thighs, and jammed his cock into my cunt. I humped him as hard as I had been humped only a few minutes ago — maybe harder. Jack recovered from the fall and returned my every thrust with a pheromone-driven frenzy. He lifted his head to meet my face so that we could kiss. I sucked his tongue into my mouth, doing my best to swallow it. His plunging cock hit me just right, which made me release his tongue. I bit down on his lip and might have drawn blood except he wrenched my head away by the ear before I could. 

I laughed into his chest as my first orgasm hit me. My eyes rolled into the back of my head as my pussy pulled me up so high that I couldn’t breathe. Higher and higher I climbed, begging for the crash. My cunt opened itself so wide that Jack’s ungripped cock flopped against its walls as he kept fucking me. And then I fell, I crashed, I took a breath only to lose it again as I moaned over my laughter. 

Jack flipped us over onto my back without missing a hump. I could feel that he was ready, I could smell that he was ready, and I was ready to take in every precious drop. I felt my next climax build with the anticipation, and was rewarded after I felt the first spurt of his hot seed. He grunted and I squealed until his balls had no more to give. I pushed him away and clamped my thighs tight together to bury his treasure. 

Jack stood up and helped me to my feet. He got water for the both of us, took his supplements, and locked the door. I loved The Heat, even though I knew I’d feel differently when it was over. 

---------------------------- 

Jack and I were fourth-generation Arcadians. Our immediate ancestors were the several generations who had traveled aboard the Ark. Before the Ark, there was the Earth. Ours wasn’t the first generational spaceship from Earth and it wasn’t the last, but it was the only one that was sent here to Arcadia. Each of those missions had their parameters, or goals, or raisons d’etre, and they chose their crews accordingly. 

Ours was a Library Ark. Again, we weren’t the first but we were the only ones in this sector, and we had the distinction of being the first Library that didn’t require population replenishments. I’m a physicist, not a sociologist or geneticist, and so I never studied the minute details related to generational ships’ crew selections. But as I understood it, the crews from the previous Libraries were chosen more for their dedication to their arts and sciences, and candidates were rejected outright if they showed inclinations outside of academia. A side effect of that algorithm was that those colonists suffered from a distinct lack of interest in procreating in general, and motherhood in particular. 

People had sex, of course, and they had babies, of course, but they didn’t have a lot of babies. Most of the women who even wanted children were content with having a baby or two, which meant that the size of their populations inevitably dwindled. 

Arcadia’s planners, however, took all of that into account when they built their selection matrix, striving for a statistically appropriate pool of their overall population to have an above-average tendency to want more babies. 

That’s when Darwin was proven right again. 

In our closed population, women who tended to want more babies had more babies, and those that didn’t, didn’t. Gradually through the generations, the majority of women wanted many babies, because the ones who didn’t want a lot of babies bred themselves out of the gene pool. To have babies, women need to have sex, and those that had more sex had more babies. When those babies grew up, the ones who craved more sex had even more sex and more babies, and when those babies grew up, the ones who craved insemination and craved even more sex, had more sex and more babies. 

As a result, natural selection tricked us into this evolutionary branch of the human female’s drive to reproduce, which we called The Heat. 

---------------------------- 

I knew that The Heat hard was on Jack, as it was for other husbands. Mostly for romantic reasons, I wanted my children to be his. I know two of my four are, and I’m pretty sure about a third. DNA testing could confirm all that, but I’m not the type to go against social taboos. Since I wanted Jack’s babies, I needed Jack’s seed, and since I’d be craving cock for a while, Jack had to be the one to satisfy my cravings. 

I stroked Jack’s cheek. “I’m so glad you got there in time to claim me.” I removed my top and tossed it and my skirt in with the dirty laundry. I would have been happy to start fucking again right away, but I managed a little self-discipline to give Jack more recovery time. I got on my knees and tucked my head under his kilt, slobbering all over his cock while I fondled it and his balls. I stuck a couple fingers up between my legs, but it didn’t do much for me. During The Heat, masturbation was about as effective as trying to tickle myself. 

“Hey, we haven’t tried that before. When your head is covered up, do you fall asleep?” 

I chuckled, despite my fixation on his manhood. I sucked a ball into my mouth, bit gently down at the root, then released it. I popped my head out from under his kilt and said, “Nope. Wide awake and ready for more.” I stood and leaned over the bed so he could take me from behind. I shivered as he slid it in and giggled when he reached the hilt. He didn’t move, letting my vagina reform itself around him, grip him, knead and caress him from within. He sighed, withdrew, and reinserted it. I rested my head on my crossed arms and let myself enjoy the leisurely love-making. “I don’t even know what time it is.” 

“It’s not even mid-day. I’ll call my mom later to make arrangements for the kids.” 

Out, in, squeeze, release. I was beginning to feel anxious but held back from telling him to do me harder yet. If we were to last through The Heat together, I needed to keep myself under control and drag this out. 

“How old were you when you started?” 

He already knew the answer; he was simply keeping me preoccupied as we swayed back and forth, in and out. “I was twelve when I had my first period. I remember how much my mom cried because I’d have to move away to a Keep soon.” I know I’ll cry when my first daughter has to leave. 

Nuclear families like ours weren’t nearly as prevalent as they were on old Earth or the first generations on the Ark. Extended clans or tribes had formed naturally and their compounds dotted the colony. I loved visiting friends at their communes with all the bustling activity. There were boarding schools as well, which were like co-ed Keeps for the youngest, and academies for boys and young men, which were called “Chivalries.” Whatever kind of family a girl came out of, we all eventually spent time at a Keep. 

---------------------------- 

I fidgeted under my husband’s gentle thrusts. “You’re going too easy, Jack.” We had learned together how to gradually increase the intensity, like training for a marathon, although my body would have been just as happy with a hundred sprints. Marriages didn’t last if the husband didn’t. 

---------------------------- 

The purpose of the Keeps was to insulate and protect young women. There were two classes of Keeps, called “Upper” and “Lower” Houses. The Lower House was for the youngest of us, where we continued our schooling with an emphasis on play. All of us knew about The Heat (how could we not) but at the Lower Houses we learned of its biology, along with the concepts of moderation and self-control. 

The Upper House was for those in their late teens and older to isolate them from men for as long as was practicable. While we sure as hell experienced sexual urges during The Heat, we didn’t lose control of our good senses until after the first time we had sex with a man. That’s not to say that there wasn’t any sex at the Upper Houses of the Keeps. Besides being taught different ways to masturbate, we did a lot of bed-hopping, especially during those special few days. Some of the best sex I’ve ever had was with young women who were going through The Heat at the same time I was.

Birth control wasn’t taught because it didn’t work. Chemicals were overridden or overwritten by our own hormones, or they just made us sick. Women willingly hurt themselves clawing out any implanted devices. Sheathing cocks was laughable, and we knew, somehow, if there was no sperm. They tried operations and chemicals, but if a man’s ejaculate lacked sperm, the men were usually physically attacked by the women as they felt betrayed or cheated. 

---------------------------- 

“Are you going to fuck me or not?” I snapped at Jack without thinking. He slapped my ass hard, red palm-print hard, and proceeded to give me the pounding I wanted. “Oh, baby, I love you so much,” I trilled. Who doesn’t love a good mood swing while getting fucked? 

---------------------------- 

Just like their occupants, the Keeps were not impenetrable. The safeguards did a better job of keeping the boys out than they did keeping the girls in. The girls were never punished for escaping, and while I never learned what kinds of punishments the boys got, I knew they never tried twice. I was one of the good girls and hadn’t sneaked out until I was seventeen. 

I remember that Kaye-kaye and I were in her bed at the Keep, lazing in the afterglow, wondering aloud what having a real cock was like. “I’ll bet they’re lying to us,” she said. I asked her what she meant, as I traced my finger up and down from her breast bone to her belly button. “I’ll bet that women don’t get all cock-crazy once they’ve had one. I’ll bet they’re only making us wait longer before we start having babies.” I agreed to be agreeable, but she did make me wonder. 

“Let’s break out,” she suggested. I used every argument against running away that had ever been taught to us, but I wanted to find out what having a man was like as much as she did. Leaving the Keep wasn’t difficult. Everybody there had heard about one way or another to get past the gates, and with very little planning we were outside for the first time in years. We didn’t know where to go or who we could trust, so we spent a lot of time hiding. 

We smelled the man before he announced himself. Kaye-kaye and I looked at each other wide-eyed and asked each other, “What is THAT?” It was, and still is, an aroma better than the most fragrant flower. 

---------------------------- 

“Make me cum, honey. Come on, make me cum!” That wouldn’t be enough — I still needed his cum in me, but a simple climax would do for now. Without missing a beat, he curved a finger in between his cock and my clit and did that wiggling thing he does so well. I counted down to zero and let the sparks fly. My knees weakened but Jack and his cock kept me propped up. The tingling traveled inward from my fingers and toes and met in a knot in the pit of my belly, where it gradually dissolved away, leaving behind the ongoing consistent, insistent fucking he was still giving me. My mind cleared up enough for us to get onto the bed and into a new position. 

---------------------------- 

“Are you girls looking for anyone in particular?” 

His voice made me jump. We spun around and saw an older man, old enough to be my dad, maybe in his late-thirties. I bit my lip as I stared at the lump in his kilt. I could feel my pulse pounding in my neck, and in my clit – my clit! I wobbled my head back and forth and Kaye-kaye stuttered, “No.” 

“Well, then, who wants to be first?” he said as he let his kilt fall to the ground. 

I stumbled towards him taking my underwear off, then fell when Kaye-kaye shoved me. “I’ll go first,” she declared. 

I got up and shoved her back. This girl and I, who earlier in the day were best friends snuggling after mutually-induced orgasms, argued and threatened each other like life-long enemies. Luckily, we caught a new scent and stopped before we could hurt each other. 

“Boys! Over here!” the man shouted. “These are my sons,” he told us as the young men that we sensed came nearer. “No need to be fighting now.” 

I left the boys for Kaye-kaye and jumped at the man, but stopped short of touching him because I didn’t know what to do. I decided to kiss him, but before I could, he spun me around with a ‘humph,’ flipped my skirt up onto my back, and drove his cock home. 

That was the first time my cunt took on a will of her own, doing everything she could for that cock, making me a mindless bystander. I stood on his feet with my arms flailing in front of me, and I would have fallen forward had it not been for his grasp on my hips and his hook in my hole. I wept as I tried to come to terms with the pleasure that I was feeling and cried out when he splashed his seed deep inside. My climax was more intense than any I had had before from touch, toy or tongue. 

That was why we were kept at the Keeps, and I cursed the Keepers for our captivity. 

The man gently set me on my hands and knees. I was simultaneously content and discontented. I needed more. The man was done but I was not. I pleaded with the man to put it back in but he shook his head. “Not right now I can’t,” he said, but I didn’t understand. 

I looked over at Kaye-kaye who was on her back with her knees up, holding onto her ankles. I was mesmerized by the steady rise and plummet of the boy’s ass and Kaye-kaye's grunts every time his pelvis smashed into hers. 

I smiled as the second son’s erection approached me, and I presented my backside for it. Before he reached me, an ambulance arrived. Two Keepers got out, and one of them shouted at us to have some respect for ourselves, but I spat out, “What does respect have to do with getting fucked?” 

“Kris, get in the truck,” she said. 

“No! You’re not taking me back to the Keep!” 

“You’re not going back,” she assured me, and then she shouted to the other son. “You! If you want her then you’ll have to do it in here!” Two other men climbed out of the back. “If you don’t want her, these men will take her,” the Keeper advised. 

The boy ran to get into the ambulance and I scrambled to follow. I hadn’t noticed exactly when Kaye-kaye and another man had joined us, and dismissed them soon after, as the truck brought us to a Dormitory. Kaye-kaye and I were friends again afterwards, and nine months later we delivered our first children, two days apart. 

---------------------------- 

I sat on Jack’s cock and my cunt gobbled him up. I tipped my head back and moaned, but he tugged on my armpit hair to break me out of my reverie, which meant he was close to cumming. I ground my crotch into his, then bounced on his lap. I lost myself in the fucking and hadn’t noticed the medics who came in with a gurney. Jack’s load was smaller that time, but it was still more than enough to trigger a climax and cool my Heat. As his cock softened inside me, and before I could feel anxious about that, a medic jabbed a needle into my neck. 

Sedatives were not very effective, and the medics had to be careful with them to avoid an overdose. I was incapacitated long enough, though, to be brought into a room and strapped onto a bed. I was confused at first, but was relieved when I saw Jack. “Where are we?” 

“We talked about this, Kris.” Jack’s voice was firm, soothing and reassuring. “You couldn’t know in advance.” He sighed. “We’re at the Heat Abatement Research Center. Look around.” 

I was in a large room with about a dozen filled beds. I focused to my left, where a woman was covered up to her shoulders with a white sheet. A nasal cannula gently hissed air, and she stared into an oval, curved dish that was aimed a few centimeters from her eyes. It was suspended by a slender arm that was tethered to a rail that ran above her for the length of the bed. A second multi-jointed arm was secured at the other end and was positioned between her legs, under the sheet. 

I saw her arms and legs occasionally jerk under the sheet. At one point, her head rapidly shook a centimeter or so from side to side and her eyes wobbled and jiggled, widened and narrowed and her lids fluttered with a wild frenzy, all the while looking into the dish. After a few seconds, she stopped and calmly stared ahead again. 

A medic told Jack he had to leave. “Jack, honey, you can’t leave.” My voice was calm as I stated the obvious. “You need to fuck me again.”  I knew it was true and he knew it. You could have asked anyone.  

He kissed me on my forehead. “I’ll be right outside, and I’ll see you soon.” 

“No. No!” I struggled against the straps. “Dammit, you’re not being funny. Get your fucking ass on top of me and fucking fuck me!” He hesitated but didn’t look back, and I lost sight of him. 

“You!” I screamed at a medic who ignored my subsequent threats and pleas. She covered me with a white sheet, then flipped it up from the bottom so that I was exposed from the hips, down. 

She affixed a very realistic dildo to the end of the mechanical arm that was suspended above me. I laughed at how stupid she was and told her so. She silently smiled to herself, spread my very wet labia apart, and slid it in. 

I clamped myself around it by reflex, tried to reject it, and gripped it again. The dildo vibrated, but that’s an oversimplification. There were complex rhythms and harmonics coming from it, like it was singing into me. I was lulled and my cunt sucked on it like a pacifier. The medic replaced the sheet and I enjoyed not being angry for a minute. I told the medic that this wouldn’t be enough. 

“I know,” she said. 

She put the cannula into place and it puffed a cool, moist stream which tickled my nose. I inhaled, caught a familiar scent, and breathed in again more deeply. “Jack?” 

“He’s just on the other side of that door, dear.” 

“But I smell him!” 

“I know,” she said. 

The dildo started thrusting maybe two or three centimeters with each stroke. Something on it aligned pleasantly with my clitoris. I felt sad, though, as I approached an undeserved climax. The medic was talking to someone else, but I didn’t pay attention until I heard the word, “ejaculate.” 

The dildo pulsed and swelled and swelled and shot a stream deep inside me. I had that orgasm and rode with it as I felt more warm fluid pump into my thirsty cunt. 

I was bewildered. “There’s no man here. This isn’t right.” I got angry again and struggled against the restraints, even as the dildo resumed its singing. The medic positioned an oval dish near my eyes, and I could see a poor reflection of them in the dark glass. “This isn’t right!” I shouted again and again, as I tried to get away. A light suddenly flashed from the dish, which startled me into silence. Then it flickered and strobed with colors and unrecognizable patterns. That’s all I remembered until I woke up. 

I woke up lying on my side and saw Jack smiling at me. I quickly realized we weren’t at home, but Jack answered before I could ask. 

“We’re still at the center. How are you feeling?” 

I told him I was good, and I was. “I slept through The Heat?” 

“Sort of.” 

I started to remember. “I could smell you, but you weren’t there.” 

“Faked. They engineered bacteria or algae or something to manufacture my pheromones, my semen, and my DNA-less sperm. The copies weren’t perfect, as you well know, but between them and some tricks with lights and sounds, they put you into some kind of trance, so you accepted it all – no drugs, just smoke, mirrors and snake oil.” 

I thought about what all that meant. “And next time?” 

“You responded well, but they don’t know what will happen with repeated therapy. It might always work, it might work sometimes, it might stop working altogether.” 

We filled out the release paperwork and I completed a very long questionnaire before we left. I peeked into the therapy dorm and imagined what I must have looked like in there. I still can’t remember anything that happened to me after the flashing lights started. 

Jack had worked so hard for me to get admitted to these trials, and I love him for it. This would make life so much easier for him — for us. It’s not like we have anything to lose. It’s not like I’m giving anything up.