The next morning I woke up to Tiff firmly shaking my shoulder.

“Get your goddamned pants on!”, she whispered hastily into my ear.

As I tried to wake up enough to resume normal human functioning, Tiff got up and flounced into the back, again dressed (if that can be even really said) in my shirt and the black g-string.

“Morning, Mom!” I heard her say, followed by some quieter chit-chat. She was giving me time to get my goddamned pants on.

With no desire to be caught naked by my own mother, I quickly grabbed my trousers and slid into them. On instinct I went to grab a shirt, before I remembered that my trousers were literally all I had been wearing for days. My dangly bits suitably covered, I headed off to the little bathroom to take care of some morning business.

Now, I’ve woken up a few times in questionable locations or circumstances, and I am not one of those people who bolts awake fully sentient. I ease into the day. I think that is why it really took until I was in the bathroom looking in the mirror before the events of the previous night hit me.

I fucked my little sister.

She initiated it, but I did it. And it was great. And horrible. And comforting. And criminal. And tender and violent and intimate and impersonal and a thousand other contradictory things all at once. I had violated a sacred trust, and Mom was going to murder me. So I just stood there and stared at my reflection and tried to snatch some kind of lucid thought out of the pure chaos of my brain.

Of course, there is only so long you can stand staring into a bathroom mirror when it is the only bathroom, so after a few minutes of silent panic I heard a gentle knocking.

“Hon? Are you okay?”

Shit. Shitshitshitshitshitshitshit.

“Yeah, Mom, sorry, I’ll be out in a minute.”

Mom was waiting outside and gave me the briefest of motherly inspections before squeezing past me into the bathroom. She startled at my touch when I tried to give her an affectionate pat – I think I was trying to remind her of my love and “goodness” against the time when she would inevitably find out what I had done. Her startle surprised me, though – it was nothing more than I had done thousands of times before, and she certainly saw that I was there, but she jumped like she had been shocked. Even with my mind raging, I noticed that was strange.

Once the water was running, I approached my sister, who was casually eating a ration bar and playing some game on one of the boards.

“We should talk.”

She looked up at me. She hadn’t jumped, but she was clearly flushed and nervous about my presence.

“No, we shouldn’t.”

“What? We need to talk about this!”

“No, we don’t. We really don’t. And I really don’t want to.”

“What about Mom? She’s acting weird, she might have heard us!”

We had both been talking quietly, and I had to hold myself back from shouting. She relaxed a little and her mouth broke into a little smile.

“No way. She was completely out of it.”, she said, turning back to her game, “With what she took, she might have heard an explosion but there is no way she heard us.”

“What?? How??”

She looked back up at me and leaned away from me in surprise.

“The dispenser. Didn’t you check it out? It’s not just ration bars, it’s also connected to the automed. It will dispense some basic meds if you ask, and apparently if you just escaped an exploding starliner ‘basic’ includes sleeping pills and tranquilizers. You didn’t notice? I didn’t think she was that subtle.”

In retrospect, I don’t think she was, I had just been wrapped up in my own issues.

“No… no, I didn’t notice.”

“Yeah, I think she was trying to hide it, I just didn’t think she was any good at hiding it.”

She had relaxed a little as we had talked, but looking back at me, she tensed up again.

“We all have things we’re struggling with.”, she said.

The rest of the day crawled by. Where Tiff and I had been spending most of our days playing games with each other, today she seemed to be avoiding me as much as she could without being rude. Mom wasn’t any more interactive, going through the niceties but frequently retreating to the “no boys” section in the rear to lay down. We all went through the basics of our routine like food, shower, and laundry but otherwise we were all just… off. And whenever I glanced at Mom or Tiff, it seemed like they were watching me.

About midday, before “lunch” and a shower, I decided to get in some exercise. It wasn’t much, basically some calisthenics and other bodyweight exercises, but it felt good to be moving and helped to burn some of the nervous energy I had been accumulating. It also got me the main area to myself, as not long after I started Mom excused herself to the back and Tiff quickly took the opportunity to indulge in a second shower, having taken the first just a few hours prior. They both emerged about 20 minutes later and seemed a little more relaxed for it. I guess we all have our ways of dealing with stress.

Things were a little easier when I got out of my own shower, but the rest of the day just saw all of us getting gradually more antsy. I wasn’t sure why, for anyone but myself, but I could tell that it wasn’t just me. They were still sneaking glances at me when they thought I wasn’t looking, and while I was pretty sure I knew why Tiff was being awkward, the only reason I could think of for Mom to watch me was that despite Tiff’s opinion she knew what we were up to. It was enough to make start to get a little paranoid, and I think we were all a little relieved when it was time to turn the lights out and go to sleep. Well, sort of.

However much I was looking forward to the sweet release of sleep and the prospect of a more “normal” tomorrow, I was still incredibly tense. Part of that I knew was that I had not jerked off during my shower – it just hadn’t felt right to do so. The much, much bigger part was that I was not sure what the rest of the night would hold.

It couldn’t have been ten minutes before I saw Tiff emerge from the aisle. She was still dressed in my shirt and the black g-string, and still looked amazing even in the dim light. Without a word, and without removing the shirt, she laid down on the bed next to me, pressing her back into my side.

For a few minutes, we just laid there, almost perfectly still. I don’t know what was going through her mind, but I was completely unsure what would happen or even what I wanted to happen, so I was waiting for some cue. When it didn’t come, I decided that her decision to remain clothed was meant to convey the message that yesterday had been a fluke, a momentary break from societal norms in the wake of catastrophe. She was again just my sister, and this was again just about comfort. I rolled onto my side to spoon her, wrapping my arms around her. For comfort.

Well, at first.

The problem was Honest Johnson. It didn’t matter what I thought, the basics of the position, and the friction, and the inability to shut the previous night from my mind all meant that not long after I wrapped her up in my embrace, my dick was again rapidly swelling towards full mast. There was no way Tiff couldn’t feel it, but her only response was to give out a contented little sigh and press herself more firmly into me. And that just made things harder.

She wasn’t gyrating into me like she had before, just pressing. The signals seemed to me very mixed, like she wanted me to do something but didn’t want to start it, or like she wanted me but didn’t want to acknowledge wanting me. For several minutes I just laid there, Honest Johnson pressed firmly into her ass as she pushed her ass right back at me. But a man can only take so much.

I made a decision.

My left arm was underneath her, my right arm wrapped over her stomach (it feels silly to call something so flat a “belly”). I folded my left arm in, bringing my hand up under the shirt until I was holding her right breast. I knew her reaction would determine what would happen that night and probably impact the rest of our lives even more that the last night’s fucking.

She moaned and began to actively grind her ass into my cock. I took that as a confirmation of sorts.

I slid my right hand down to the g-string and slipped it underneath as she lifted her leg a little to help me get access and bit her lip to stifle a moan. Her shaved pussy was already wet, her clit prominent and so sensitive that when I found it she dropped her mouth to my arm to help stifle her squeal. I started to rub her clit, with enthusiasm if not (to be honest) any particular skill, squeezing her tit and rolling her little nipple between my fingers. She moaned and writhed in my grasp as I started to finger fuck her under the g-string, Honest Johnson dry humping her ass cheeks in anticipation.

“What do you want”, I whispered into her ear. I’m not sure why I asked, I think I just wanted some verbal reassurance that I wasn’t raping my little sister.

She didn’t answer.

“Do you want me to fuck you?”

She bit her lip again, her only sound a low involuntary moan.

Something about her silence was throwing me off. Last night she was practical, straightforward, looking for a physical release from her mental trauma, just like me. Tonight she was almost shy, reserved, but despite her silence she had come back to the bed where we had fucked, had pressed herself into me.

An idea started to form. Last night was purely physical, urgently needed release from the stresses of the disaster, decided on the spur of the moment. Tonight wasn’t. Tonight she was trying to tell me something, or trying to decide something, or perhaps trying to tell me something.

And yes, by the way, I DO think this much when I fuck. Deal with it.

She was making her body available to me, that much was very clear. She could have rejected my advance, or left my bed, or never come to it at all. The question was what else she was offering. There were a couple of ways to find out, but I took the easiest and least risky.

“Do you want me to use you? To take you?”

Her eyes had been closed the whole time, but now they screwed shut. Her head dipped towards her chest, her lips clenched, and she nodded her head a few times with a small, quick motion.

That was enough for me!

I rolled myself off her and pushed her over onto her back. I slid off my trousers and pulled down her thong, fighting the urge to tear it off, conscious of our limited clothing supply and the difficulty in explaining that to Mom. For a split second we were both still, her lying there, legs together, hands clenched into loose fists over the shirt at her breasts, me kneeling in next to her legs. I pulled her knees apart and shuffled between her legs, my cock larger than her forearm, and laid it on top of her pussy. I began to stroke back and forth, feeling her moisture lubricate my cock, feeling the little shudders she gave as I sawed my dick across her clit. She didn’t resist or say anything, she just took a deep breath, clamped her lips in her teeth, and looked into my eyes.

I remembered her exhortations of the previous night, her urging me not to be gentle. So I wasn’t.

In one long movement I shoved all 30cm of Honest Johnson into her tight, teenage cunt. The sound that escaped her clenched lips was a muted scream, enough that if I wasn’t so entranced by the feel of her pussy squeezing the full length of my cock I probably would have panicked at the thought of Mom’s almost certain alarm. She turned her head and shoulders in some attempt to press her face into the mattress, but I wanted to see her, I didn’t want her to hide anything from me. I grabbed her wrists and pressed them into the mattress over her head, forcing her body flat as I began to stroke hard into her.

She shut her eyes tight and arched her back suddenly, and for a moment I thought I had gone too far, that she was trying to escape, before a wet gush at my crotch made me realize that she had already hit orgasm. She was thankfully silent, sucking air into already full lungs and then holding it tightly as it washed over her to the tempo of my still-pistoning cock. I could feel her arms trying to push me away, not with the full force of someone trying to escape, but with the pressure of her whole body spasming in pleasure. I watched her the whole time, seeing that night what had been turned away from me the night before.

As she slowly came down, her body began to relax. She opened her eyes and stared into mine, still not saying anything beyond some involuntary noises. I stopped stroking, paused long enough to pull the shirt off of her and toss it aside. She started to cross her arms over her perfect tits, so I again grabbed her wrists and forced them to the mattress. She didn’t really resist so much as she made me do it. I had asked her if she wanted to be taken. Apparently she did.

I brought her hands together over head so I could grip her two thin wrists together in my left hand and begin to explore her body with my right. Her tits, her ass, her stomach, I let my free hand roam as I continued pounding into her. She didn’t struggle against me, her movements were reactive or even cooperative, trying to find her pleasure and mine. It didn’t take much longer before I felt her body stat to tense again as she drew in a deep breath. Remembering the night before, I brought my right hand over her mouth just in time for her to scream her next orgasm into it. I noticed she was crying. It didn’t stop me.

We continued like this long enough for her to cum several more times before I finally began to erupt. I pulled out and shuffled up her body until my cock was just at her chin. Stroking it firmly, I passingly remembered her concern the previous night, her not wanting to dirty the mattress, but knew that wasn’t the reason. I just wanted to cum in her mouth, see her swallow it again.

I leaned forward, her arms still forced above her head, and pushed the head of my cock between her lips. She didn’t resist, nor did she break eye contact, just tipping her head enough to allow easy entry. Her lips clamped around the tip of my cock as I started to shoot cum into her mouth. She swallowed each delivery, didn’t let a single drop escape, staring into my eyes the whole time.

I wasn’t finished. I had learned long ago that my modifications let me go repeatedly in a short span and I meant to exercise that ability. When the last drops had left my dick, I pulled back. I’m not sure if she thought I was really done or not, but I didn’t mean to give her time to think about it. Letting go of her wrists, I reached down to her hips and casually rolled her onto her front. With that glorious ass presented to me, I began to push my cock into her pussy from behind. I saw and heard her clamp a hand over her mouth as she groaned with the sensation. I reached out and took her hair in my hand, that massive braid becoming a rope to her head, pulling it back.

She shuddered and shook her way through several more orgasms as I pulled her hair or her arms so that her whole upper body just jutted out from mine as I pounded her cunt over and over again. She didn’t tell me to stop, or ask me to slow down, or resist what I was doing, she just took the pounding and reaped her pleasure. Every time she hit an orgasm I brought her arms tightly behind her back, forcing her face into the mattress where her muted screams made the whole mattress vibrate.

I had been resisting cumming again, thankful to the engineers who had made my orgasms a mostly conscious decision, but I was starting to wonder how much more she could take. I flipped her over again onto her back, pulled her legs straight and over my shoulders, and pulled her arms straight and down against the mattress, my hands and her wrists at the level of her ass. Kneeling in that position I began to jackhammer slow, powerful strokes, coming almost entirely out of her each time before slamming back in with full force. I felt her start to tighten up, felt her arms in convulsion trying to tear themselves out of my grasp. Letting abruptly go, I lowered myself on top of her as she wrapped her arms around me, kissing her eagerly and feeling her respond, our tongues darting over each other, screaming into each other as she came on my cock and I sent a full load right into her pussy.

I pistoned a bit with each spurt, and felt her orgasm hit a little peak with each thrust, clenching my cock each time. Slowing gradually down, I finally came to a stop and relaxed. She didn’t. She clenched me with her whole body, and after a few seconds I realized she was sobbing into my chest.

I wasn’t quite sure what to do, but she was clinging to me with a strength I didn’t know she had, so I just laid there on top of her as she silently wept. I think we stayed in that position for almost fifteen minutes before she finally relaxed and allowed me to lift my weight off of her. As I raised myself up I tried to look into her eyes and was relieved when she met my gaze. She smiled, a little laugh mixing in with her diminishing sobs.

“I’m okay. Really. There’s just a lot… and that was so… It’s okay.”

“Okay?”

I was relieved that she wasn’t upset or hurt, but her response somehow hurt a little. That had been “okay”??

She heard the question in my voice and pushed herself up to kiss me, her smile broadening.

“I’m okay. You were amazing. Christ, that almost made getting shipwrecked worth it!”, she said, brushing the tears from her eyes.

I grinned.

“Well… okay then!”

I kissed her again before slowly pulling myself off of her. After so long in that position, it was a little difficult, our sore muscles and the awkward position making us fight to uncouple ourselves. Whatever fantasy we had had about keeping the mattress clean had lost to the reality of a dozen or so orgasms, and it felt like half the surface was sticky. She surveyed the damage and then handed the shirt to me.

“Get this wet.”

I nodded and set off for the sink. I watched as she used my pants to mop up the loose fluids as well she could, and then used the damp shirt to clean up the rest as well as she could. A few rinses in the bathroom sink to repeat the process and she was satisfied. Taking the damp, sticky clothes in her arms, she turned to me and smiled.

“Come on. Our turn now.”

As the laundry performed its usual miracles with our garments, we showered together. Our hands explored each other bodies as we exchanged gentle kisses and firm embraces as we triggered the shower system through wash, rinse, and dry cycles. We walked out of the shower and dressed in our newly-laundered clothes, before walking back to the bed. I don’t think her eyes left mine the whole time.

She settled into my side once again, her body wrapped around me, her head on my chest. I held her in the gentle warmth of the room, stroking her hair and back. The shirt didn’t bother me at all.

She turned her face up to me, her eyes starting to cloud with the same fatigue that was washing over me.

“I love you.” She whispered.

“I love you, too.”, I whispered back. We had told each other that before. This time felt different.

I felt her breathing settle into the depth of sleep, marveling in the feel of her body fit so perfectly against mine and reveling in that blissful fatigue of truly great sex. In no time at all, I drifted off, content and spent.

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