I never intended to continue writing Warmth, it was considered one-shot from the beginning. However, recently I realised that it could become so much more. This is the result.

This fic wouldn't have been created without extensive help from Dioxine, who practically co-authored the plot and suggested numerous details. Also many thanks to Shadowfox026, who did some excellent work as a beta reader.

In case you haven't noticed, the rating is M this time. Seriously. You probably know what the reason is. :q

3rd July 2020, Tokyo

Kagami was usually jogging early in the morning, when the temperature was moderate and the usual humidity of Tokyo air was still bearable. It was also easier and less embarrassing to do it when everyone else did. Many people her age would run at a steady pace along the Arakawa river, while the elderly were practicing tai chi in shaded parks and squares, and occasional teenagers were zipping around on bikes and roller skates; then in the blink of an eye they would scatter to workplaces, schools and shops, leaving the pathways for the heat to reign supreme. No sane person would be exercising outside at this hour, not during summer anyway, unless they were aiming to become some sort of iron man.

Kagami did not have such plans, but today she went jogging anyway. It simply turned out that she wouldn't have time to in the morning, and she feared the consequential feeling of guilt more than the stress of working out in the afternoon sun. Still, Kagami was left gasping for air as she was climbing back to her apartment.

With one last effort, Kagami stumbled inside and closed the door, feeling a cool breeze coming from the air conditioning. Her clothes were completely soaked with sweat, and her short hair was sticking to her scalp, but she didn't mind; all she could think of at the moment was to stop her racing heart and burning lungs from trying to torture her to death. She reached to take her shoe off, but her strength finally left her and she crumbled to the floor unceremoniously.

Having gathered herself a little, Kagami started undoing her shoelaces. She knew she should get under the shower as soon as possible, but she wasn't ready to get up yet. Was she pushing herself too hard? Trying to maintain her figure was fine, but she felt like she just did something stupid; normally she didn't wear herself out so much.

Trying to get the runners off her aching feet, she glimpsed her own reflection in the long mirror she normally used to prepare for work. What she saw was the familiar face, now flustered and open-mouthed, framed with short hair that even Tsukasa instantly likened to the one sported by Nagato Yuki from the old Suzumiya series. Her body was athletic and lean, something she was proud of, and her leg muscles were especially prominent in this moment of exhaustion. She looked better than any time before, which was something few thirty-year-old women could say.

The problem was, there was nobody to show it off to.

Kagami sighed, and managed to drag herself up from the floor, then to the bathroom. The day was too bright and cheerful to feel depressed, but mild depression never left Kagami these days. Well, maybe it was more of a constant feeling of emptiness, occasionally punctuated with work-related stress... She was alone, simple as that.

Fifteen minutes later, Kagami was sitting on the sofa wearing her white tracksuit, waiting for her hair to dry and smoking a cigarette. Hot water soothed her body and gave her a sense of tranquillity, but also brought her unhappy thoughts even closer to the surface. She reckoned it must have been one of these days, nothing more.

Half-consciously, she looked towards her working desk, above which hung one particular framed photo, one of the few things in her possession that dated back to her school days. Her younger self was surrounded by three other schoolgirls, all of them seemingly at the brink of bursting with laughter — perhaps except for herself — and simply radiating happiness.

The photo was ridiculously frilly, including lots of little pink hearts and a bright yellow background, but she'd always somehow felt deeply attached to it. In college, she thought of it as a touching keepsake, which she sometimes used to improve her mood if she needed; later it simply became a reminder of her cheerful, happy land of youth where she never was alone, a land lost in the seas of mundane.

Standing behind her was Miyuki, the studious and polite young lady who never seemed to be affected by anything. This was the least painful one; Kagami liked and respected Miyuki, bur they never were very close, and she hadn't, in all honesty, known her Miyuki very well. The other two were different cases though.

Konata... Konata was her best friend then, and actually the only person she could call that, ever. Yes, she was annoying and eccentric at times, but she was actually listening to what Kagami had to say and could come up with a coherent answer. The most important thing though was that Konata was simply fun to be with, someone who accepted Kagami the way she was and never ignored her feelings. She still couldn't understand how they'd fallen apart so badly after school, over matters that were ultimately trivial. They still sent each other New Year greetings (often via Tsukasa), but they both seemed reluctant to look the other one in the eye. They hadn't seen each other for almost ten years.

And finally, Tsukasa. Sweet, innocent Tsukasa, truly the closest person she'd ever had, and from the very beginning. Of course they were still pretty close, but their lives became so completely different that she felt she lost something precious in her relationship with Tsukasa. When Kagami was busy with her management career, Tsukasa married one of her former classmates and started a nice, proper family; she'd already had one boy, and was hoping for another child. Kagami usually saw them during Sunday dinners, since Tsukasa's family was living in their parents' house, and could see very well how happy and complete Tsukasa felt about her life. Kagami was happy for her too, but it was somehow painful that she lost her Tsukasa to someone else.

What is wrong with me exactly? Kagami asked herself, not for the first time. Konata and Tsukasa have always been the ones she scorned for not being serious, and therefore at risk of not getting anywhere in lives. Now they were both married (Konata even twice actually) and as far as she could know perfectly happy with their life choices, one becoming a housewife and the other running a small manga online store, while she herself was as far from fulfilment as se could, despite her rather satisfactory and well-paid job. Was she right to criticise them in the first place? Maybe she was the one who didn't understand? Maybe she was just stupid?

Kagami forcefully extinguished her cigarette. Brooding over it all would solve nothing, it was action and common sense that always kept her going. Sure, not everything in her life was perfect, but there wasn't much she could do about it now. She needed to find something to do, and quick. Perhaps some house chores would be in order? She had gotten quite good with those over the years.

She settled on washing windows in the living room. It had already been a month since the last time.

***

Kagami was leaning against her favourite window and smoking. The view outside was really pleasant; there was a busy road shielded with soundproof screens not far from her apartment, and just behind it Arakawa river could be seen in all its glory. The river wasn't very big by any means, but the new commercial district on the far side and its image reflected in the calm waters mixed well with the greenery and bicycle tracks, creating a sense of modernity. Not many people could afford this kind of view, and certainly not many single women.

"Maybe I'm not feeling much better", Kagami said aloud, "but at least I have clean windows."

She genuinely hoped to find something else to do, but she couldn't think of anything. Finally, Kagami settled on checking her mailbox. She came downstairs and peeked inside, hoping to find her precious little grey envelope, but there was none; the only thing she found was a small folder, advertising some sort of beach hotel on Shikoku. A perfectly happy family with two kids was smiling at her, partially submerged in a heart-shaped pool, while a yellow building occupied most of the background. Typical junk mail around these parts.

Kagami double-checked contents the of the folder. The place seemed pleasant enough, and despite being quite expensive it was perfectly affordable to her. Why not take a holiday during summer? she thought, but quickly dismissed the idea. She only had one week of holiday per year, and she would be spending it with her family. Besides, who would she go with? Tsukasa certainly wouldn't have the time...

For some reason Kagami felt worse than before, and dragged herself back to the apartment. Feeling completely empty and unable to do anything, not even to read a book or check her email, she plopped down onto the armchair and switched the TV on.

That helped; she felt her conscience being slowly dissolved by the usual crap that dominated the TV these days. She'd never been an avid watcher, and in her opinion the average program quality deteriorated rapidly since she was a girl, but she didn't care at the moment. Kagami devoted her whole attention to some show with contestants trying their best with paper and scissors, trying to produce various sorts of paper clothing and putting it on a hostess who just stood there with a bright smile. A lively, short announcer kept throwing witty comments at their attempts, and commercial brakes seemed to chime in every five minutes or so.

That hostess looks a bit like Tsukasa when you think about it, thought Kagami. I wouldn't actually mind cutting some sort of paper clothes for Tsukasa, and putting it on her like that...

Kagami had no idea how long she was staring at this, but she snapped out of it immediately when her cell phone rang. She reached for it; the number was Tsukasa's.

Kagami felt her heart thumping. She raised the phone. "Hello? Kagami here."

"Good evening, sis!", said Tsukasa's cheerful voice. "How was your day?"

Kagami was close to saying "Not much, as always", but she felt it wouldn't be too nice. "Hello, Tsukasa. Well, it was all right. I returned from work, jogged a little, cleaned the windows in my living room, and now I'm watching TV."

"That's nice."

"Yeah, I guess... How about you, Tsukasa?"

"It was fine. I went shopping with mom, then we made some lunch, and dad was busy with the garden so I helped out, too... We're waiting for Minoru now, he should be back from work early tonight!"

"Oh. That's great."

"Anyway sis, I just wanted to ask if everything is fine about Sunday? The dinner will be starting around four, but of course you can come earlier if you want..."

Right. Sunday. Not a normal dinner this time, but a birthday party. Their thirtieth birthday...

"Oh, sure. I'll be there around noon, I'm sure you can use some help with cooking."

"Hehe, don't worry about that. But still, please come!"

"I'll be there, Tsukasa. I'll call you Sunday morning, in case we need to buy anything."

"That's a good idea.... Um, see you Sunday, then!"

"Yeah, see you. Don't exert yourself in the kitchen."

Tsukasa giggled. "Bye then, sis."

"Bye."

Even though the call was over, Kagami kept staring at the cell phone for quite some time. Her thirtieth birthday... It sounded like a death sentence. Sure, she was still young, but she knew deep down that some things cannot be undone; her life was, more or less, a failure.

And Tsukasa... She loved her so much. Back in the old days she never understood how much she loved her, but she did nonetheless. Without her, she felt incomplete, or perhaps without a purpose. She utterly missed her.

Kagami sighed and turned off the TV, now disinterested. Perhaps she should go to sleep now, but the evening was still young; she wouldn't be able to fall asleep. She wasn't even interested in getting herself drunk tonight. Hell, she should make the bed anyway.

Kagami got up to go to the bedroom, but she somehow stopped in front of the big mirror. She suddenly remembered the origins of her own name, Kagami. Her father explained to her once that according to the old beliefs, some mirrors were inhabited by gods, who would show the truth to those they deem worthy of such knowledge... or such punishment. She glared at her image.

"So my life sucks. Can you fix it, almighty goddess?", she asked bitterly. Her reflection didn't respond, only mimicking her own words.

Kagami knew that no divine power in the world could save her from herself. She understood now the true meaning of the story about mirrors: it was she, and only she, who could do anything to help her. After all, it was her own reflection that lived in the mirror. And there was nothing she could do anymore.

Kagami turned away, but at the last moment she decided to give the mirror a second look. The sun was setting, and its golden rays were flowing into the living room, both obscuring the image in the mirror and giving it an eerie glow. In Kagami's eyes, her reflection wasn't much different from how Tsukasa looked...

Intrigued by the thought, she paused to ponder it. She wasn't exactly like Tsukasa obviously, but still they were rather alike — especially now, when Kagami's hair was of similar length. When she narrowed her eyes, it was quite easy to imagine it was indeed Tsukasa .

Kagami found this thought strangely comforting, or at least attractive. She tried a few facial expressions she associated with her twin sister, and after some practice managed to convey a rather convincing image of Tsukasa. She improved it further with the right body posture, cutely slouching a little bit. She wasn't sure why she was doing this, she even felt it was a bit silly, but something pushed her forward to try harder.

The clothes... Tsukasa doesn't wear tracksuits, thought Kagami. This needs to be fixed...

Kagami carefully drew the curtains, plunging the room in relative darkness. She then opened her wardrobe and started digging. There were a few things she never wore, things that she would be embarrassed to be seen in, but that were definitely Tsukasa style. She managed to find a dark yellow summer dress with a dark green flowery pattern, reaching to about half her thigh, which she quickly changed to. She returned to the mirror and saw that her effort paid off: what she could see was closer to the original than she hoped. She was almost a spiting image of her sister.

Tsukasa... Tsukasa was everything Kagami wanted to be, and couldn't. She was warm, light-hearted, graceful, and attractive. Despite not being too concerned about her weight, she radiated some subtle aura of sensuality that made her an object of many advances... An aura Kagami was beginning to recognise quite clearly, too.

She was aware the Tsukasa she conveyed was only a poor imitation, but she was getting more fascinated with that image with every heartbeat. She was absolutely unable to explain to herself what she was doing, and why, but she paid no attention to such details for the moment. She knelt on the floor gracefully, mimicking Tsukasa's genuine smile and innocent look. She felt hot, and her limbs trembled slightly, but on the other hand she felt very much in control. It was magical; dangerous.

She wriggled her body a little, looking at her curves like she never did before. Does Minoru look at Tsukasa like that? It felt like a major violation of Tsukasa's privacy to examine "her" body like that, and it felt both terrible and wonderful...

Kagami's hands started to move around her body, while her eyes remained glued to the mirror. Even if she could think straight now, she still couldn't tell why she was so excited: was she aroused by Tsukasa? Or by the thought of being Tsukasa? Or was it something else entirely? But she wasn't thinking about this now, she was thinking about her dear sister.

Her hands were getting bolder now; she felt them caressing not just her sides and thighs, but also cupping her left breast and rubbing her neck. It felt good, but it looked even better. "Tsukasa" was slightly panting, her mouth half-open, her white panties clearly visible between her thighs and her body slowly rocking back and forth, radiating a powerful aura of dark sexuality. Nobody on Earth could resist this image, and Kagami wasn't going to anyway.

She wouldn't remember when exactly the panties would come off, but it was not a moment too soon. Kagami couldn't remember being that aroused before. Self-satisfaction certainly wasn't unfamiliar to her, but this experience exceeded every fantasy she'd had. It wasn't long before she came violently, the image of her sister burned into her mind and engulfing everything else with its dark fire.

***

After a while, Kagami dragged herself off the floor. The enormous orgasm was gone, but her mind was still dizzy from the shattering experience. She was still unable to comprehend what she did, but she understood one thing: she missed Tsukasa like never before.

Leaving her dress and underwear forgotten on the floor, Kagami entered her bedroom and sat on the bed. She lit a cigarette, and exhaled a small cloud of smoke. It was almost dark now.

"Tsukasa...", whispered Kagami. She felt abandoned and deceived; not by her sister, but the world in general. It was terrible feeling.

She finished her last cigarette of the day and lay down on the bed, not caring about finding any sleeping clothes. She was tired, really tired; she just wanted to forget everything, and especially her own existence. However, sleep wouldn't come — everything that happened that day kept whirling inside her head, denying her rest. She was simply too anxious to fall asleep now, and too concentrated on that very special person she couldn't let go of.

"Tsukasa...", she whispered again. She would see her sister the day after tomorrow, but somehow she felt it wasn't enough. Somehow it would never be enough, unless she could hold Tsukasa in her arms forever. She was fully aware of how crazy it was, but their separation burned her almost physically. Were twins meant to go through things as painful as growing up?

Kagami found herself crying. Her tears were falling on the pillow in silence, as she gripped the bed sheets with all her might. She knew she was losing it, badly, but it changed nothing; she was suffering from what could only be called acute loneliness: this empty feeling that had been accumulating inside her finally managed to manifest tonight. She didn't want to be alone; she wanted to be saved.

Kagami knew it was wrong, absurd, and childish. However, she could only withstand so much. She grabbed her cell phone and selected Tsukasa's number.

"Hello...?", came a sleepy voice.

"Tsukasa..."

"Sis? What is it?" Tsukasa sounded a bit alarmed.

"I'm... sorry to disturb you at this hour, but... I miss you, sis!", Kagami groaned, not exactly believing she was doing this.

"Sis! Are you crying?!"

"Uh..."

"Are you allright?!"

Kagami didn't respond; she couldn't lie at the moment, but she couldn't make her sister even more worried either.

"Sis... I'll be there in half an hour. Wait for me, please!"

Kagami really wanted to actually say something, but before she came up with a coherent response, the call was disconnected.