AN: The chunk in italics at the beginning is copy-pasted from In Flight, as you've probably guessed. You will have to have read at least up to Chapter 18 of In Flight for this to make a blind bit of sense to you.

The Black Sekirei had come into my home. Having invited her into the lounge for tea (as was only polite) she provoked a display of violence on my part, and in my proximity I became aware of a flush to her cheeks, and a shortness of breath. Thoughtlessly exclaiming at her reaction, the members of my flock present reacted as one could expect. Musubi was ecstatic, Tsukiumi's ire rose and Akitsu maintained her vigil. Karasuba, however, did not come to be winged and Musubi's reaction was strident.

"Stop that!" she shouted, her voice unreasonably loud. "Stop talking like that! Karasuba-sama," Karasuba twitched, honest surprise on her face at the interruption. She had probably never seen her friend act like this before. "You're reacting to Shirou-san! This is your chance to be with your Ashikabi, your destined one! Stop acting like you're not going to accept it!"

"Muu-chan," Karasuba murmured, a thoughtful look on her face. On my right Tsukiumi was also staring at the angry Musubi. The water user was more used to the irrepressible and bubbly version of the shrine girl, not this new furious Musubi. The only one in the room not staring at Musubi was Akitsu, the snow woman's eyes still locked firmly on Karasuba in an unwavering vigil.

After spending what seemed like an eternal moment pinned by her friend's angry glare, Karasuba smiled, her eyes crinkling as she did so. "But if I did that, Muu-chan," she began. "It would interfere with our promise."

"This is more important than the promise! This is about your finding your love," Musubi declared, and Karasuba's smile slipped slightly. "Love is more important than anything else!"

"Not to me," Karasuba's simple response caused Musubi to stumble as though she had been physically struck by the slim Sekirei. "To me, the promise is much more important."

Desperately, Musubi turned to me, her expression twisted in frustration. "Shirou-sama," she pleaded with me. "Please, Shirou-sama, wing Karasuba. If it's you, I'm sure she can find love." The shrine girl sounded like she was in physical pain as she begged me to help her convince her friend to be mated to me.

I knew that, in another life, I would have immediately denied her. But as a ripple in the ocean can grow into a mighty wave, so too did a seemingly inconsequential burst of curiosity in the week before cause me to hesitate where I would otherwise not have, and remember a conversation I would not otherwise have had.

It was in the days immediately after my winging of Matsu and, closer to the subject, the revelation of my meeting with Karasuba. That particular conversation had stuck in my mind, niggling, because of a source of incongruity I couldn't quite explain. Most of my flock reacted about as I expected them to, in the face of the knowledge that their Ashikabi had been in the same room as the Black Sekirei, and had in fact pegged a steak knife at her face. Shock, fear, anger and a certain degree of awed incredulity. It had taken a good while after before any of my Sekirei had properly calmed down. Akitsu and Homura especially.

Musubi on the other hand reacted...with curiosity and excitement? I would not have expected her to have the strongest negative reaction to the story, but even with her naivete and innocence I would have expected her to frown upon a figure as blood-soaked as Karasuba.

So one evening, accompanied only by Akitsu after coming home from that day's work, I managed to isolate the shrine girl in the corridors on her way to whatever errand Miya had set her.

"Musubi-chan? Do you have a moment?"

"Of course!" she chirped, and skipped back down the corridor to me "what is it Shirou-san?"

"I was just curious" I began, carefully picking my words "Do you know Karasuba personally?"

"Ah! Yes! Karasuba-sama saved me, then visited a lot while I was recovering!"

That certainly perked my interest. Not to mention my concern. But she didn't seem bothered my the memory, presumably having dealt with whatever it was long ago, so I tentatively pressed on "Saved? Recovering? from what?"

"The experiments!" The shrine girl chirped, apparently completely ignorant of the dire implications.

And didn't that send a jagged chill down my spine. I could feel even the normally impassive Akitsu tense at my side, though her distress was likely based on the more obvious of the implications.

Had the mages association found them already? I quickly reassured myself that that couldn't be true. There would be far less Sekirei remaining and MBI would be far more paranoid from rampant disappearances if that were the case. So that left foreign nationals and other organisations within Japan. which begged the question of how they'd found out without the Mages Association learning of the Sekirei's existence, but I could investigate that later if necessary.

For now though, with that specific concern assuaged (though something about the way she had said it tickled at the back of my mind...), I pressed on with my inquiry "So you're good friends with Karasuba?"

"Yep!" after her confirmation, all at once the energy seemed to drain from Musubi, lending a startlingly melancholy cast to her features "Karasuba-sama needs friends..."

Though my original question had been answered, the curiosity that statement engendered pushed me along "Why's that?"

"Karasuba-sama only had one friend before me, and Yume-sama died saving me" She seemed to shrink even further into herself at the admission "I don't know what she was like before, but the Karasuba-sama I know is like a child. She hates and hates, and refuses to see how love can strengthen and support you when nothing else will!" the shrine girl perks up, and clenches her fist before her "So I made a promise with her! We'll fight and fight, until we're the only two Sekirei left and then we'll fight! If I win that will prove that I'm right, that love is stronger than anything, and I can set the rest of my fellow birds free"

The certainty and uncharacteristically quiet resolve behind the declaration left me speechless. It seemed a serious Musubi was something I wasn't quite ready for. Despite my speechlessness, Musubi's usual good cheer quickly reasserted itself and she grinned up at me "It's a big dream, but with your help, I know I can do it Shirou-sama!"

Shaking off my startlement, I smiled down at her "Yes, you can. Thank you for telling that to me Musubi-chan. Now go on. I'm pretty sure Miya's waiting for you"

And so, she had skipped off with her usual energy and, as I cooked that night's dinner, I pondered the ramifications of that conversation. However, uninformed as I was, nothing beyond reinforced certainty that conflict with the Black Sekirei was inevitable came of my rumination.

Not until a few days after, and another declaration by Musubi viciously tore down my presumptions of my position. Then it inspired yet another realisation in my beleaguered mind.

All the Sekirei I had met, on reflection, were driven on some level by love. In Musubi's case it was obvious, she lived and breathed love to a level that convinced me she was more similar to me in all the wrong ways than anyone realised. Akitsu shaped her behaviour, her clothing, everything about herself in order to best emulate the sekirei's pinnacle of love. Homura chose a career based on what could best enable him to find his soulmate, and fought tirelessly to enable other Sekirei to find theirs even as his lack tore him apart. Matsu constantly seeks physical consummation, and wasn't above an attempt to manipulate me in order to help me perform better in my role as their leader and mate. Even Tsukiumi's apparent resentment of the need for an Ashikabi was not what it seemed, but a defense mechanism behind which she hid crippling fear and a classically tsundere incapability to deal with her emotions. Miya's very essence had been coloured by the loss of love.

Love and the pursuit thereof is a driving force among Sekirei, far beyond what it is to humans. It is a point on which they can all relate to one another, a unifying factor that, In the absence of the Sekirei plan, would bring them together.

And Karasuba, if I understood Musubi correctly, rejected it entirely.

It makes understanding the distaste all the other sekirei feel for her all the easier, even ignoring her head count. It's like humans with a known clinical psychopath in their midst, that disturbing sense that there's something fundamentally wrong with that person, something fundamental that they don't understand. And in Karasuba's case, this is compounded by the way she lashes out at the world. Very much like the child Musubi described her as, Karasuba takes out her frustration, hatred and grief on the people and world around her because, lacking any balancing factor, that's all she knows how to do.

In her own way, Karasuba's as broken and needy as Akitsu. But dug into the rut of self destructive beliefs and posessed of power and will enough to keep those who could help at bay. Seeking through mortal combat with the legacy of her lost friend affirmation of those beliefs and a way to cut ties with her completely.

Karasuba was someone who needed to be saved. From herself, but saved all the same.

And so, where I would otherwise have refused Musubi's desperate plea outright, I instead turned to Karasuba and began to make my case.

"Actually Karasuba, you're kind of wrong"

She daintily lifted a single eyebrow "Oh? how so?"

"Your promise with Musubi was that, when you were the only Sekirei left, the two of you would fight, yes?" Karasuba nodded slowly, evidently unsure where I was going with this "both of you being winged to me wouldn't necessarily make that impossible. In fact it would enable you to make more certain that you reach that point"

Her eyebrow raised further "You would so willingly let two of your sekirei fight? That's pretty callous of you Shiroi-chan. I'm surprised" judging by the discomfited fidgeting to my right it seemed Tsukiumi, likely to her consternation, agreed with the Black Sekirei.

"Obviously I insist that it not be to the death, but it was a promise the two of you made before I winged either of you and so my right to interfere only extends as far as ensuring any parties winged to me do not leave with permanent injury, and that issue will remain whether I wing you or not. Also, like I said, joining my flock would better enable you to ensure Musubi-chan's continued growth. You don't necessarily need to coddle her, but just making sure she doesn't get in over her head, a helpful training hint here and there, stuff like that" I stopped for a moment to take a sip of tea, keeping my eyes on an increasingly contemplative Karasuba.

"And what about my duties in the disciplinary squad? Surely you don't believe MBI will take it well if my Ashikabi is not an employee"

"Well, I certainly wouldn't stop you from carrying those out. And if you're already winged, well, what can they do?"

It was a good question. They could send the full might of MBI's military force down upon us, but even if they did so while we were outside of Izumo house (which I suspected would be the case if it did happen) the concentration of force I and my flock bring to bear would result in massive casualties and to what end? The removal of one slightly unfair participant in a competition already stacked against the majority of it's members? Hell, I bet Minaka would have a whale of a time with the instability this winging would induce.

Even the minor point of any possible bias on Karasuba's part is moot. The only jobs I suspect she took any real interest in were the ones where she was required to eliminate particularly unruly contestants and why would they believe I'd object to that? All they'd really have to do is keep her off missions with a bit more subtlety and even if she does go on an unauthorised rampage they can just pin it on me as her Ashikabi.

I can see it on Karasuba's face as these points occur to her one by one, each pushing her on the teetering edge of indecision. And then Musubi, adorable, love worshipping, apparently-more-manipulative-than-I-thought Musubi, astonishes me for the second time that day.

"Shirou-san? Do you know how to make apple tarts?"

I blinked at her, nonplussed "Um, yeah. I mean, I'd need to buy some apples and cinnamon, but what does that have to do with..." I trailed off as I noticed, with some degree of consternation, that Karasuba was cackling into her hand hysterically.

"Only you Shiroi-chan...only you would lure an innocent maiden into your harem with promises of pastry"

Innocent? "Well, you know what they say about hearts and stomachs" That was what tipped her over the edge? Well, that would explain the laughter at least "So you've made a decision?"

"Yes" having apparently calmed down, she settled back and looked me dead in the eye as a worryingly predatory grin spreads across her features "I'll take a gamble on you, Shiroi-chan"

"Well then" I tried to ignore the practically vibrating Musubi across the table "Shall we?"

Compared to those so far, Karasuba's winging was a short and remarkably chaste affair. There was a moment toward the start where she perceptibly had to wrench control of herself back, but compared to the tender moments with Tsukiumi and Musubi, and the tonsil tennis that was Matsu's winging, it was very mechanical. As if she understood the mechanism of what she was doing, but not what it was supposed to convey. Which, I considered as she pulled back, wings of a liquid, inky black already fading, was likely the truth.

And then Musubi decided she couldn't keep control of herself anymore.

"KARASUBA-SAMAAAA!" She squealed and pounced upon her new flockmate, launching into a fresh tirade on how much fun she believed they were going to have together while, astonishingly, Karasuba seemed to lose a degree of her composure, an almost imperceptible blush spreading across her cheeks.

As that hilarity went on, I turned to my two quieter companions. Akitsu still had her eyes on Karasuba, her doubts apparently not assuaged by the winging, that heartrendingly familiar touch of bitterness visible in them. Tsukiumi on the other hand had her eyes trained firmly on me, in a glare which convinced me that I'd have to explain my plan in full later.

Which was fine. I'd planned on explaining my conclusions to my flock ever since I'd made them. And if Karasuba did next what I believed she was going to then this would provide a perfect opportunity.

When I turned back to the scene across the table, Karasuba had finally extracted herself from the pile of excited Musubi under which she'd been buried and was looking outside.

"Well, my kimono's probably dry by now, so I should really be getting back to MBI" She drawled, picking herself up off the floor.

"Huh? Why?" Musubi whined, not yet ready to let her friend leave.

"I need to get my affairs in order, check in with the bosses and all that" then she turned to me, her earlier predatory grin reasserting itself "and it will be the perfect distance to watch the fireworks"

"Fireworks?" I asked "is there some kind of festival no-one's told me about?"

"No" the Black Sekirei chuckled, her grin spreading "but I'd love to hear how you explain all this to 01"

01? Did she mean Miya...

...oh...

...fuck.

AN: So that's my interpretation of Karasuba. A broken ex-tsundere who can't decide whether she loves or hates Yume. By this interpretation, and that's what I based the decision she made on, the duel with Musubi is a way of letting go and more important to her than working with Natsuo to do something spoilerrific. If Karasuba wins, then that proves Yume's values were bullshit and Karasuba can merrily hate her guts (because life and emotion are obviously that simple [/sarcasm]). She genuinely loves a good fight, but a lot of her behaviour is a defense mechanism.

Also, unless I work up the effort to plan out all the effects of this winging on the plot, this will remain a one-shot. If you want to take a crack at your own full-length version, feel free. Just be sure to PM me about it so I can read it.