Disclaimer: Kubo is the Allfather Odin of this universe. If I'm anything, it's a very tiny Loki, just occasionally twisting his domain around for my own amusement.

The Three-Body Problem

A Bleach Fanfic

Chapter Three: November

Jinzen was a particular challenge for Uryū.

This wasn't because he had any difficulty accessing his inner world—he'd been able to do that for years. Obviously he'd been the first in the group to manage it, something Renji had apparently demonstrated by snapping his fingers in front of Uryū's face several times for the benefit of the rest of the class.

Or so Karin had told him, anyway.

The problem was rather that now, nearly three months into this whole endeavor, everyone else was at least in occasional contact with the spirit of their zanpakutō, and Uryū had yet to even find his.

Today would apparently be no different. He entered his inner world, blinked to adjust to the light, and found Lucia in the exact same place she'd been since the first time he'd ventured into Soul Society. He assumed that a zanpakutō spirit would manifest much as she did—a roughly human shape with some obviously symbolic characteristics, like the prominent Quincy cross on Lucia's full-body cloak.

She was the only thing in his inner world at all, as far as he could tell, and she never moved, so Uryū used her as a point of reference, striking out in a different direction from her each day, searching the endless white until his eyes couldn't stand the strain, extending his spiritual sense as well, just in case, and coming up with absolutely nothing. Not even a blip of reiatsu or the faint outline of a person.

To make matters worse, he still couldn't perceive depth at all, and so sometimes he turned around and swore that Lucia had only grown smaller, not more distant. He had no way of knowing how far he'd searched, how far he could go, or even if he went anywhere at all. The completely flat brightness of the inner world gave him no reference, and he occasionally became certain that he must be walking vertically rather than horizontally, only the feel of it didn't change at all. It was disconcerting at best.

Uryū found himself abruptly jolted from the Jinzen when something hit his body with enough force to register, a burst of pain in his head. Lifting his fingers to his temple, he touched it carefully and grimaced. No blood, but he was probably going to bruise. No object to correspond to the blow. Someone had hit him with a Hadō. A small one, and not significant enough to pose any true danger, but a Hadō all the same. Probably a Shō.

Surreptitiously, he glanced around. There were a few people in the class who could cast Shō without the incantation, naming it quietly enough to go unheard by others. He obviously hadn't done it to himself, and he knew Yuzu would never. That left two that he knew of. Abe, the oldest student in the class, wasn't the type. If he had a problem with a person, everyone would know about it, because he'd be public and overt. That left Fujita.

Uryū's eyes fell on her, seated in perfect seiza, apparently deeply intent on her meditation. For a moment, he wondered if he must not be mistaken. But even though he hadn't been aware enough to notice the fluctuation in reiatsu, he had been pulled out of meditation by a heavy impact—the pain in the side of his head was enough proof of that.

Slowly, Fujita cracked a dark eye open, fixing it directly on him, leaving him with no further doubt. She had done it, and she'd done it intentionally.

Uryū scowled, making to rise to his feet.

"All right, everyone, that's enough for today!" Renji called the end of the meditation, letting his reiatsu fluctuate just enough to gain the attention of those who were still pretty far under. He fixed Uryū with a flat look, shaking his head just slightly.

"Ishida, you got a minute?"

Uryū conceded, diverting his attention from Fujita, now filing out with the others, and fixing it on Renji. "Of course."

Renji folded his arms across his chest, waiting until everyone else had gone before speaking. "What was that?" He asked the question without any apparent accusation, only a slight angle to his head.

"It's not important," Uryū replied. His problems were his to deal with, whatever issue Fujita took with his existence included. Though there was really only one issue it could be.

Renji lifted a hand to scratch at his forehead. "Seemed pretty important to me. And that's a hell of a bruise you're going to have there in a bit."

"I'll deal with it."

The fukutaichō sighed heavily. "Yeah, okay, whatever. But fighting between students is a big deal here, and you don't wanna be breaking that rule. Most people would get warned the first time. You might not."

"Because I'm a Quincy." Uryū felt his lip curl.

"Yeah, pretty much. That's the way it is. Doesn't mean it's right, but you're only going to get so much leeway, and it's less than everyone else. Got it?"

"Yes." Uryū half-turned, intending to take his leave.

"Hey, hold up. That's not actually the reason I asked you to stay. Follow me for a sec."

"I'll admit, I was pretty surprised when I heard you were here." Rukia smiled widely, bringing the apple she held to her mouth and biting down with a crisp snap.

Uryū settled beside her on the roof, choosing to sit at the apex of the frame rather than laying along the angle, as she did. He glanced at Renji for a moment, assuming he'd been the one to inform her of the situation.

"Well… Urahara-san can be persuasive. Especially when Yoruichi-san is helping."

She swallowed, rotating the apple in her fingers to get at the next red part. "That I can believe. Still, it's… weird, is all. Seeing you in an academy uniform, with a zanpakutō."

"I think so, too," he conceded readily, lifting both shoulders.

"How are you finding it?" Another crunch.

Uryū had to give that one some real consideration. In some ways, his negative expectations were bearing themselves out in reality. Most of the other students didn't talk to him, and gave him a wide berth in the hallways. A fair number stared, and most of those were either hostile or afraid, that was easy enough to tell. The hostile ones, like Moribito and Fujita, made his life more difficult, and the frightened ones just made him uncomfortable.

But it wasn't all bad, he supposed. The Kurosakis were easy to get along with, though he did wonder if he might not be making things more difficult for them in the long run. It was surely not unnoticed that they associated with him, and already they were starting to catch some flak by proxy.

"It… will take some adjusting, yet." If he even wanted to adjust.

"Yeah… I felt the same. For different reasons, but still." Rukia peeled flesh off the apple with the reflexive efficiency of someone used to making food count.

"It's even worse in the first class, sometimes," Renji put in knowingly. "Everybody in there's got something to prove. Noble brats, Rukongai mutts, all of 'em trying to outdo each other at everything. You learn your stuff faster just to keep up, but it can get kinda ugly sometimes."

"I have a feeling I know who's who by now," Uryū said, tone dry.

Rukia tilted her head, an invitation for him to elaborate.

"Nishimura's noble, and so is Fujita. Moribito, too, but less. He tries harder and more obviously than they do. Tojo and Matsuda are the most relaxed, which I'm guessing puts them somewhere in the middle. Abe and Sugitani are from the outer districts."

"Huh." Rukia blinked once. "Fujita? You wouldn't be talking about Fujita Ume, would you?"

"I believe that to be her first name, yes. Why?"

Rukia huffed, clearly amused. "It's just that the Fujita are one of the vassal clans of the Kuchiki. I've met her before; she's unpleasant."

"That would be an accurate characterization of my observations as well."

Rukia rolled her eyes. "Well, as someone who's used to dealing with people like that, I can tell you that the best thing to do is ignore them. They don't like it when you do that, and if they can't get a rise out of you, they usually stop trying after a while."

"Eh. Being nobility kind of sounds like it sucks," Renji said, flopping backwards and sliding down at the same time so he was also reclining with the slope of the roof.

Rukia didn't seem to have much to say to that.

"You get some weekends off and stuff, don't you, Ishida?" she asked instead, glancing at him from the corner of an eye.

"On occasion."

"You should come out to Rukongai with us. There's a small group that gets drinks and just hangs out or whatever. It's pretty low-key, but Matsumoto was talking about wanting to meet you, and so now Hisagi and Kira do too."

That sounded like exactly the type of socialization Uryū had spent most of his life consciously avoiding. He really didn't want to be stared at by more shinigami or have intrusive questions leveled at him, and he wasn't especially fond of doing any of it with alcohol involved either.

He nodded anyway. "I suppose I could."

"You don't have to make it sound like a chore," Rukia said, but she grinned at him. "I'll have Renji let you know when the next one is."

Karin's footsteps were heavy on the ground, intentionally so. She led Yuzu down the boys' corridor, counting doors until she came to the one she wanted. Not bothering to knock, she pulled at the handle, marginally less angry when it didn't turn out to be locked. "Ishida!"

He started, head whipping to the the side quickly, alarm scrawled over his features for half a second before he smoothed it over again. "Karin-san?"

On the other side of the room, Matsuda rolled over slightly, but did not wake.

"You're good at hakuda. I need you to make me better at it so I can kick Moribito's ass." She said it as bluntly as she said everything else, crossing her arms and leaning her hip against his doorway.

"Are you sure you want me to—"

"Yes. I'm sure. You're better than the rest of the class, and that makes you best to practice with. Plus, Yuzu needs to run more laps and I know you're still pissed that Fujita's better at kidō than you." Her mouth dropped into a scowl. "We all need more practice. It'll work better if we do it together."

Karin had always preferred team sports, and that was the reason why. Even if everyone on a team had different skills and was better at different things, the whole group got better if they helped each other out.

Plus, everyone else in the class was still treating this like an individual game, and that was stupid.

"All right," he agreed. "How about tonight, on the track? We can bring a mat for hakuda and some of the portable kidō targets."

Karin tried not to smile, unsure if she succeeded. "Yeah. Let's do it."

Yuzu straightened from her toe-touch, twisting her torso around to the left, and then to the right. She wouldn't last very long at all on the track if she didn't stretch first. She probably wouldn't last that long anyway, come to think of it. But she'd resolved to do the extra practice, and this way she could run while the other two were doing hakuda, and be done in enough time to help with the kidō.

Better to end the whole thing with something she actually liked, right?

So while Karin practiced trying to throw someone half a foot taller than herself, Yuzu coaxed her body into a jog, remembering to pick her feet up a little more and trying not to lament her apparently permanent snail-pace.

She'd made it once around the track by the time she realized she wasn't alone anymore.

"Sugitani-san?" Of all the people in her classes, Sugitani talked the least, and she had no read on him at all. She certainly hadn't expected to find him out here on the track near midnight, swinging his arms with exactly the casual ease she envied.

He didn't look at her, but he did tilt his head slightly in her direction. An acknowledgement, maybe. Something about him always seemed quite… intense, and it was enough to dissuade Yuzu from attempting much by way of conversation.

Well, that and the fact that she really needed to save her breath. Still, her father hadn't raised her to be rude, and so she gave him a smile as he passed her. "Good luck!"

Fixing her eyes on the track in front of her, Yuzu reverted to the breathing pattern Karin had told her to use: in through the nose, out through the mouth. In through the nose…

What did people do when they ran, anyway? Should she think about something else? What if she tripped? She really didn't want to fall on her face with Sugitani somewhere around. Humiliating herself in front of her sister and Ishida, who she knew and was fairly comfortable with, would be bad enough.

Three laps in, Yuzu felt her breath begin to tremble. It was harder and harder to pull them in steadily, and she forgot several times to close her mouth on the inhale. She was getting better at this, maybe, but it was still the most unpleasant thing she had to do in any class, and at least once a week, she seriously questioned her decision to be here. Maybe she wasn't really cut out for this shinigami business; she knew her temperament could definitely be better-suited.

Perhaps she should just… go home. Go back to helping her dad at the clinic, and occasionally recall the bullet she'd dodged by not actually waiting to fail out of the academy, or worse, freeze up in a combat situation. This was real life and death, after all, and the only reason she was here to begin with was that Karin hadn't wanted to take the entrance exam alone. She hadn't said it, but Yuzu had known, and acted like she wanted to do it too.

She'd expected to fail it.

Yuzu stretched her stride a little, feeling the sweat begin to gather at her back. Really, the only reason she wasn't so sure quitting was the right thing was because they'd probably take her asauchi back, and she'd had several nice conversations with it. Weren't they supposed to be part of a person's soul after a while? Would she feel empty and strange if she gave it up? She couldn't shake the feeling that she would.

Her shoulders relaxed slightly, feet plodding along the track in steady rhythm. But of course… then she wondered if maybe that wasn't the point. Once you reached a certain point in the training, was there any going back at all? Was it a way of guaranteeing that people joined the forces in the Seireitei?

It sounded like something Ishida would say, but that didn't make it wrong.

The stitch in her side was acting up, but Yuzu tried to breathe smoothly through it. Just a few more laps, and then she'd be able to justify taking a break. It was fortunate, she thought, that eventually her spiritual energy would begin to fortify her physical abilities, as soon as they learned how to use it for that.

Apparently, though, conditioning her actual body was the first step. Yanagi-sensei had made it very clear that the better shape she was in, the more reiatsu-fortification she would be able to handle, and the easier it would be to use. Shunpō was only the beginning, which explained all the laps during his class.

Moving her arm to her side, Yuzu brushed over the hilt of her zanpakutō. A little frisson of something passed through her, a wordless encouragement, and she lifted her hand instead to brush a few loose hairs out of her face. She didn't have to push herself beyond her limits every single day—that would be worse for her in the long run. But doing just a little more each time, ignoring the pain in her ribcage for just a little longer… she could do that.

"Ow." Karin wrinkled her nose from her spot on the mat, tipping her head back to look Ishida in the face. "How are you good at this? You're a stick." It was an exaggeration, but not that much of one.

Ishida leveled her with a distinctly-unimpressed look. "And your tact is as delicate as ever," he replied flatly. He stepped back, though, giving her space to climb to her feet. "In any case, brute force will only take you so far in hakuda. It is good for blows to be strong, but more important that they are precise, and best utilize the momentum of combat. Fēng-sensei is even smaller than you, but I've no doubt she could topple people much more physically imposing without difficulty."

"Yeah, but that's what I don't get. Momentum? I know what that is, but I don't get how to use it here. Isn't hand to hand just hitting people so it hurts?" She'd seen the aftermath of enough street brawls in the Rukongai to know what they looked like. "I wish she'd just teach us how to use reiatsu in a hit. I bet I could knock him out in one punch."

Ishida sighed heavily. "And what if something came along that was stronger than Moribito, then?"

Karin blinked. "…more reiatsu?"

She scowled under the look he gave her. "I know, I know. But that guy pisses me off so much I just want to—"

"Why?"

"Eh?" Karin halted mid-explanation and looked up, catching Ishida's eyes. "Why what?"

"Why is it so important to you that you beat him? Has he said something to you?" He sounded… suspicious? Wary? She couldn't decide what the tone meant; it was too carefully-contained.

She shook her head, uncurling her fists. "No, but I can see him thinking it, you know? And that smug look he gets on his face every time he knocks me down—like I'm a bug and he's being nice by not stepping on me."

Ishida broke eye contact, glancing away. His eyes narrowed slightly. "…that might change if you started associating with different people." His posture was unnaturally stiff, making him look even more awkward than he usually did.

Karin punched him in the stomach.

It wasn't a great hit—he'd obviously been surprised, though he'd stepped into the blow apparently by reflex—but she made solid contact, and he doubled over partway, arms wrapping around his abdomen.

"Sorry. It's just it sounded like that was about to turn into a 'don't hang out with me, Karin, because I'm such an outcast and people hate me so they'll hate you too' speech. And that would be a waste of perfectly good air." She shook out her hand. Damn. He might look like a stick, but hitting him hurt.

He was staring at her, mouth slightly ajar, glasses askew and several hairs knocked from their places. "You—"

"Ishida." She crossed her arms over her chest. "Not everyone hates you. And I don't want to be friends with anyone who does. So put a cork in it and teach me about this momentum stuff."

He straightened, evening out his glasses and getting back some sense of equilibrium. Clearing his throat, he nodded. "Of course."

"Um, so… the thing about kidō is that you have to maintain concentration all the way through. It doesn't get easier after it starts—actually, the more power you put into it, the harder it is to contain." Yuzu rubbed awkwardly at the back of her head. "So… until the moment you release it, your focus should be directed inward, in a way. I'm sorry; I'm not explaining this very well."

Uryū shook his head. "No, I think that what you're saying makes sense. We should concentrate on keeping the spell stable until release."

"Right!" She visibly straightened, dropping her hand to join her other one, folded neatly in front of her. "You don't have to force it. Just guide it. If you have enough reiryoku to do the spell, it'll happen. It's just better to get the timing right, and try not to lose any of the power before releasing the charge. Weak kidō are either the result of not enough reiryoku or not enough control of it. If you have the second problem, just adding more energy won't help."

Karin frowned. "Can you show us? Maybe with a spell that we can see before it's done?"

Yuzu nodded. "Sure, okay. Uh, if you want to move over this way, I promise not to hit you with it, but it'll be easier to see than from behind…" She gestured to a spot on her left.

Uryū shifted over, Karin beside him, and tilted his head, focusing his senses on what Yuzu was doing. The difference between using reiryoku and reishi was still posing him some problems, but he suspected that if he could get a better idea of what the real difference was in the way they were channeled, the obstacles would disappear in short order.

Extending both hands, Yuzu held them at chin height, forming a rough triangle by angling them so that her index fingers and thumbs almost touched. Her shoulders lifted and settled backwards as she pulled in a deep breath. "Ye lord! Mask of blood and flesh, all creation, flutter of wings, ye who bears the name of Man! Inferno and pandemonium, the sea barrier surges, march on to the south! Hadō #31: Shakkahō!"

As they watched, a ball of red light, faintly tinged with magenta, formed in front of Yuzu's palm. At first the size of a peach pit, it wobbled for a moment at the edges, then steadied, expanding in size like a soap bubble, but never losing the near-perfect spherical shape it had. The fluctuations in Yuzu's reiatsu were minimal; she moved energy into the spell at a very steady rate, and it grew accordingly.

At the moment of release, the sphere was about as big as her head. When the incantation finished, Yuzu's reiatsu surged, pushing the spell away from her and releasing it at the same time. Only then did the Shakkahō gain the flamelike edge it was known for, and flew unerringly towards the target at the far end of the field, bathing the ground beneath it in eerie light.

It hit square in the middle of the target, obliterating the whole thing and singeing the edges of those immediately to either side upon impact.

Uryū's brows approached his hairline. "That was very impressive, Yuzu-san," he said, blinking downfield at the smoking pole where the target had been. It had also been exceptionally informative, and rather illustrative of what she'd been saying.

"When did you learn 31?" Karin added, eyes wide.

Yuzu coughed, and it was hard to tell in the relative dark, but her face might have gone pink. "I borrowed a copy of the Kidō Encyclopedia from the library. Kozu-sensei said it was okay, as long as I practiced safely."

There was a short pause, and then Uryū stood. "Well, I think I'll try as well, though perhaps with a spell slightly lower on the list. Karin-san?"

Shaking herself, the other twin nodded. "Yeah. But you've got to watch us, Yuzu, and tell us what we're doing wrong."

"I… okay," Yuzu agreed. "Ishida-san, why don't you try first?"

Karin didn't really understand her inner world all that much.

It had taken her a long time to even find the place, and now that she was here, it didn't make a ton of sense. It was a flat plane, mostly, with the springiness of turf under her feet without any actual turf. The sky above her seemed to go on forever, thick with grey clouds that moved past slowly, only to be replaced by more of them. The ground was pockmarked, like several asteroids had at some point slammed into it, leaving it cracked and pitted. She'd stood next to one of the holes once, looking down into it, but it was dark and she couldn't see how far it went.

Without even a stone to drop down and listen for, she wasn't going to risk the exploration just yet.

It had taken her a couple of weeks to find her zanpakutō spirit, but it hadn't been too hard in the end—it was a bright red against the grey and bleak blue-black of everything else.

It was also a bird, which she privately thought was kind of lame. It looked like a cross between one of those parrots from Madagascar in the living world—Yuzu had told her the word was macaw—and a crane of some kind. It had a triangular head with a skinny yellow beak, a long neck, a red body with a few yellow or orange bits, and a really long tail, almost like a peacock but without the fan thing. Which was good, because if her zanpakutō spirit was a peacock, she was going to demand a new asauchi.

At least it didn't look as silly as Zabimaru. Renji had manifested his zanpakutō for a demonstration yesterday—as soon as she got over being surprised, she'd had to work pretty hard not to laugh. The way he'd scowled at her made it clear that she hadn't totally succeeded in stifling her amusement though.

But seriously, part of his soul was a baboon with a snake for a tail.

So maybe a bird wasn't that badass, but at least she didn't have to worry about monkey jokes.

The spirit watched her with one black eye as she approached, plopping herself down crosslegged in front of it.

"So. You gonna tell me your name today?"

It blinked. "Unlikely." It had a feminine voice, but she knew Yoruichi—she wasn't going to make any guesses about what gender it was until it said so or she got its name.

"Why the heck not? I found you, I keep finding you, we've been talking in circles for a month now. What do you want, anyway?" Karin crossed her arms, glaring at it.

Not one of its feathers so much as ruffled. "If I just told you, I wouldn't get it."

"Ugh. I hate riddles. Why can't you be straightforward?"

"If I just told you, you wouldn't get it."

Overgrown chicken thought it was damn clever, didn't it? Sighing heavily, Karin flopped backwards onto the springy not-turf, keeping her arms folded over her chest. "Well, come on then. Do that thing where you ask me stupid probing questions and I hate it."

Renji had said that sometimes zanpakutō felt the need to draw answers to such questions out of their wielders, in an attempt to push the wielder into necessary growth. Karin wasn't sure she believed that, but at least it would do more than spit witticisms and platitudes at her.

"Your friend with the glasses asked you an interesting question the other day."

Karin half-raised herself at the shoulders to look over at the spirit's face. "Ishida?"

"Mm. He asked you why you need to defeat the other boy so badly." The bird arched its neck, picking its way over to her side on long, graceful legs, so that it could more easily peer down at her face.

"Yeah, and I told him."

It settled on the ground, folding its legs underneath it. This close, she noted that it was warm, like a sun-baked stone. "In a way, yes. But here is a better question: why do you feel the need to be the best?"

Karin stiffened. "I don't," she replied, unusually slowly.

"Oh, so you didn't take the standing record for shikai as a personal challenge, then?"

"I… that's not the same as wanting to be the best. I just think it's good to have goals, is all." She turned her face away slightly, looking down the nearly-featureless plane that served for ground here. It was so flat she probably saw miles ahead, until it grew totally indistinct near the horizon point.

"Goals that, upon completion, would make you in some measureable, acknowledgeable way better than everyone who came before you," the spirit persisted.

Karin groaned, separating her arms so she could cover her face with her hands. "It's not like that, okay? You don't get it. It's not about 'best.' It's just… I just…" She clenched her jaw.

"I'm not having this argument with you right now. Just leave me alone. It's not fair that you can ambush me when I'm sleeping."

She heard a rustle when the spirit rose to its feet.

"As you wish, but you will have to answer eventually."

Karin rolled over onto her side and willed herself out of the inner world.

She woke, still groggy, in her own room.

It was hard to tell what time it was, but if she took a guess, she'd suppose maybe four in the morning or so. She could make out the others in the gloom; Yuzu was tucked into the fetal position on her bed, both arms wrapped around a stuffed lion with a fluffy orange mane and brown plastic eyes that caught the spare light coming in from the window.

Situated in the center of the room was Ishida, gangly limbs folded into the cot they'd dragged in from their father's clinic about a week ago, when going back to his own room yielded strangers passed out on his bed often as not. It probably wasn't comfortable, and he still huffed about 'propriety' at least once a day, but at least he knew for sure that no one else had drooled on it… or worse.

The dormitory wasn't really meant to hold three people, but they made due.

Even though their house was big enough for each of them to have their own space, Karin and Yuzu had always shared. Karin had never in her life slept completely by herself in a room. To have one more person was just a little extra white noise to her.

One more light to chase away the dark.

"Shut up," she whispered, squeezing her eyes closed. Pulling her blankets up to her chin, Karin lay awake for a while, listening to the steady sounds of their breaths, and the gentle rustle as Yuzu pulled her knees in tighter towards her chest.

In time, as it always did, sleep found her again.

Term Dictionary:

Shakkahō – 赤火砲 – "Red Fire Cannon." It's Hadō #31, and produces a ball of red fire of varying size. It's one of the go-to offensive spells in the series.

Man, I love these kids. They have some serious issues to work out, all of them. My hope is that those issues are distinct and interesting, because the majority of this fic revolves around taking steps to solve them, and also worldbuilding. Though other characters will be making (hopefully) amusing appearances in future chapters.

Also, it has been brought to my attention indirectly (mostly by reviews) that "Karin and Yuzu do Shin'ō" is a whole subgenre in Bleach fanfic. I didn't know this, though I probably should have. I've read surprisingly few fics in this fandom, which might make me a bad fan/writer/whatever. :/

In any case, my aim in pointing this out was to apologize in advance for any similarities this bears to any other story in its subgenre. Because I haven't read such stories, I have no earthly idea how well-trod these particular paths are, and so if my selection of zanpakutō or plot points or abilities or whatever bears a resemblance to someone else's, I am sorry, and I hope I can be forgiven for not reading all of the rest of these works just to make sure I'm doing something different.

My gratitude and affection to those who've taken the time to review. When I run out of self-generated motivation, I think of you guys first, and keep on keepin' on.