Today was a very important day for Hinata. This day only came once in someone's life, and there were those who considered it to be the point at which one stopped being a child and became a woman (though typically one would be a bit older at this point, and more experienced). She was excited, and anxious, and wished there'd been more she could do to prepare. But she was here now, she trusted Naruto as much as anyone in the world, and if everything went well, this day would mark a permanent change in their relationship.

Before she'd started getting to know Naruto, she'd always assumed that she'd be doing this with Kurenai-sensei, in accordance with unspoken but near-universal ninja tradition. Though she'd thought it would be years before she had the confidence, or perhaps that it would never happen at all. She certainly wouldn't have expected to find herself here at the age of twelve, in a remote corner of the little-used Seventh Training Grounds, with her Byakugan on to make sure of their privacy, and Naruto lying on the ground in front of her looking rather stunned. (She'd tried to be as gentle as possible, but there were some things you just couldn't do gently, and he himself had insisted that she not hold back.)

Yes, this was the day Hinata presented her master with her first original technique.

A couple of seconds later, Naruto picked himself up off the ground, a little unsteadily. "Can you show me again, in slow motion this time?"

Hinata obliged. Her open-palm strike went for his solar plexus. Then, at the last second, her arm jerked back with unnatural speed, and instantly came in again, stopping just beneath his chin.

"Gotcha. So this is what you've been working on, is it?"

Hinata nodded. She'd practised it over and over before this meeting, but she'd still been afraid up to the last second that it would have some incredibly obvious flaw or counter that would make Naruto stop her before she'd even finished demonstrating. Now, she was feeling flushed with success.

"I was reading," she explained, "about how many of the oldest martial arts styles are supposed to imitate the movement of predators, and it made me wonder why there were so few based on prey. I think people underestimate how much effort a prey animal puts into surviving when it's always surrounded by bigger and stronger things that want to eat it."

"I see. So how does that translate into an unblockable death strike?"

"Well," Hinata went through the motions again as she explained, showing the way it could be adapted to strike at different points, "it's about turning escape into an offensive move. You project chakra from your palm as if you were doing water walking or tree walking, only you do it as soon as the other person starts blocking your attack, and you do it in a sharp burst. Your arm snaps back, and now you're in the starting position for the real attack while they're still in the middle of blocking your feint. Unless they're literally twice as fast as you, they've got no hope of defending."

"Nice!"

Naruto's satisfaction washed over Hinata like a warm glow (in addition to the existing warm glow that had lasted ever since the date and showed no sign of going away).

"All right, let me try it myself," he said. "Multiple Shadow Clone Technique!"

As Naruto practised against Hinata, a small army of shadow clones did the same thing in pairs around them. Every few seconds, one would disappear, and the pairings would adjust, until finally there was just one shadow clone left, who summarily dispelled himself.

"That should be enough," Naruto announced. "I do like the idea, but I'm afraid it's an incomplete technique. You can't use it."

And there it was. "What's wrong with it?"

"Way too much strain on the elbow, or any joint that has to take the impact of snapping back. If you did this on a regular basis, you'd have severe joint problems pretty soon. I bet that's why the Hyūga don't already use it, what with pure chakra emission being your thing and all."

Hinata's good mood vanished as if it had never been. Of course she wouldn't be an inventor like Naruto after a few short months. Who had she thought she was kidding? How had she even missed such an obvious weakness, when as a Hyūga she probably knew more anatomy than most chūnin? And he must have had such high expectations of her, and now she'd let him down, and managed to simultaneously disappoint her master and embarrass herself in front of her new boyfriend, and maybe she should just leave now and not waste any more of his time...

Some of this must have shown on her face.

"No, no, look, it's all right to invent incomplete techniques!" Naruto told her, waving his hands in a slightly panicked fashion. "What matters is that you keep trying, and... and don't give up, and learn from your mistakes, and..." From Naruto's expression, he was as aware as she was of how reassuring those platitudes didn't sound.

"Here, I'll give you an example," he changed tack. "Do you remember being taught the Rule of Stability when we learned the Substitution Technique?"

The ABCs of ninjutsu, at least, were something even she couldn't get wrong. "Never use an unstable substance such as a liquid or gas when anchoring yourself in real space."

"OK, so I never got taught that."

Hinata's mouth dropped open.

Naruto shrugged. "I'd broken Kataoka-sensei's niece's nose in a fight the previous day, and I think he was still a bit freaked out. So he arranged it so I got taught it on my own, and 'forgot' to teach me a couple of the essential principles. It's the kind of thing that happened when I was at the Academy."

Hinata was still giving him an incredulous look. "But... But if you break the Rule of Stability, you explode, or your body gets lost in phase space, or something terrible happens to you!"

There was a pause.

"Are you sure it wasn't an accident?" she asked, not so much doubting Naruto's account as requesting reassurance she already knew she wasn't going to get.

"Yeah," Naruto gave her a wry look, "just like when we were learning about explosive tags and someone 'accidentally' happened to give me a real set instead of replicas. Would you believe there was a time I thought everyone went through this sort of thing, like the Academy was culling people who were too careless to be ninja?"

Hinata's brain was frozen. Naruto seemed to be describing some completely alien parallel universe. She couldn't imagine living in a world where teachers tried to kill their pupils; it was like that dystopian novel where instead of being reformed, the Village Hidden in Bloody Mist had conquered the entire continent (and after reading twenty pages, Hinata had decided never to trust Shino's book recommendations again). It was what you got when you went out of your way to write grimdark, not something that happened right here in everyday life.

She tried to think of something to say, and failed. Her mind was completely blank. Naruto wouldn't lie about something like this; it wouldn't make any sense. And it was horribly consistent with the various comments he'd previously made about his childhood. Except she couldn't picture stern yet kindly Kataoka-sensei (who'd always had a soft spot for her) as some kind of cold-blooded murderer of children.

She tried hard to calm herself. The world she lived in had turned out not to be the world she knew. What did you do when the ground beneath your feet disappeared? What other foundations of her life might turn out to be lies?

However, Naruto went on, oblivious to her distressed state (or, the low-self-esteem voice in the depths of her mind whispered, simply unwilling to deal with it).

"That's why when I got taught the Substitution Technique, the first thing I did was sit down and try to think through the obvious failure modes. It didn't take me long to realise that if you could really Substitute with anything, people would be Substituting with air all the time, and there'd be no need for things like the Body Flicker Technique. So I knew right then that I hadn't been taught the whole thing.

"But long story short, I filled in the gaps as best I could from books and copying the other kids and pretending I was so dumb they had no choice but to correct me. And obviously I didn't dare experiment with the incomplete version of the technique until later, when I had clones to do it with. All things considered, I really wish they'd taught us the Clone Technique right at the beginning. It would've made my life a lot easier."

Naruto turned to look directly at Hinata, his voice rising a little. "But the point is, there's something I discovered only because I knew an incomplete technique. Wait till you get a load of this!"

He frowned. "It's probably a very big deal, though, so it needs to stay an absolute secret."

Hinata nodded, curiosity temporarily distracting her from her inner turmoil. "I promise."

"Great. Then use your Byakugan one more time to make sure no one's watching."

A quick scan of the area later, Hinata nodded again.

With a grin, Naruto summoned several ordinary clones—not shadow clones, Hinata noticed, which was unusual for him. With that effortless synchronisation unique to clones, they began forming seals, familiar and yet somehow slightly off.

"Uzumaki-style Ninjutsu: Dimensional Anchor Technique!"

Hinata blinked. Her Byakugan was still on, and suddenly she could see that a large section of the clearing in front of her was filled with a faint mist of Naruto's chakra. But it wasn't moulded into elemental chakra or anything, and try as she might, she couldn't see what the advantage was of creating clones only to make them commit suicide. It didn't help her concentration that, according to Naruto, someone she trusted had intended to turn him into mist like that.

"Awesome, isn't it?" Naruto beamed at her. "I've checked around, and I haven't been able to find a single existing technique for efficiently spreading your own chakra over a large three-dimensional area. All the techniques I've heard of are about transforming it into something else, or charging it with special properties, or infusing it into objects or whatever. Even the Hyūga stuff you've shown me is about projecting small bits of chakra with pinpoint precision rather than anything like this."

"Isn't that because neutral chakra doesn't do anything on its own?"

Naruto's grin got slightly wider. "And that's where you'd be wrong. Go on, see if you can figure it out."

Hinata tried. In addition to being an instruction from Naruto, it was an excuse to postpone having to turn her worldview upside down. Plus, she'd done little but read in the library during the couple of months after the... misunderstanding, and her understanding of general ninjutsu theory had grown fairly solid.

She'd watched his clones use the incomplete Substitution Technique, and then vanish as chakra burst into existence elsewhere. Based on what Naruto had said, they'd been violating the Rule of Stability, so presumably they were trying to anchor to thin air instead of a solid like the classic log. Which meant that when the chakra reached its destination, it tried to assume the unstable pattern of the air, failed, and dispersed into the surrounding environment. Without a stable anchor to come back to, the clones would either remain trapped in phase space forever, or they would come back in pieces, though she wasn't sure what made the difference.

If you were trying to disperse chakra across an area, why do it in this roundabout way instead of simply making clones and letting them pop?

As she pondered Naruto's chakra, she realised that it still wasn't fading away. Normally chakra from destroyed clones vanished almost instantaneously. Naruto wasn't adding any more chakra, or indeed doing anything at all, and there was nothing special about this clearing, so something about the chakra itself was unusual.

Hinata focused her Byakugan. Observing chakra flow on the finest scales was hard, much harder than mustering the level of concentration needed to follow it through a human body, but her father had been clear that someone unable to maintain flawless one-point focus could hardly be called a Hyūga at all, never mind an heir. With this hard-earned ability, Hinata could now see that the chakra was sort of... pulling itself together, not enough to counter its natural tendency to drift apart, but enough to slow the process down significantly. Almost as if it was intelligent.

Which, of course, it was. It possessed no apparent will separate from its master's, and did not respond to any attempts at communication, but this intelligence was the reason that mere hand motions and visualisation were sufficient to bring forth effects that even the most cutting-edge commoner science couldn't begin to replicate. The academically dominant Mechanical Theory of Ninjutsu in fact suggested that the Sage of Six Paths had invented ninjutsu as a user interface to allow human beings to give instructions to chakra, like clone AI programming for the very lifeforce that animated all living things.

In short, Naruto's chakra, now fully separate from him, was still following the last instructions it had received from the incomplete Substitution Technique, namely to form a stable anchor at a given location. The next question, naturally, was what this accomplished.

Hinata risked a glance at Naruto, who appeared to be giving her a measuring look. The sudden sharp awareness that this was a test (how had she not realised earlier?) doubled her heart rate. Now she had to get this right, and the faster the better.

He'd called it the Dimensional Anchor Technique. What did that mean? It didn't mean he was anchoring one dimension to another (which wasn't even a coherent concept), or that he was anchoring a location in one to a location in another (because he was explicitly failing to create a working anchor). Was he anchoring an object from moving between dimensions? But you couldn't do that with a D-rank technique. The laws of physics explicitly permitted space-time ninjutsu, and altering them even in a small area took advanced sealing techniques; a genin doing it would be like having Tora the cat perform Kiba's Beastman Clone Transformation. Although this was Naruto she was dealing with...

While Naruto still hadn't told her about his A-rank mission, the rumours were beginning to spread. Hinata had now been informed that, among other things, Naruto had single-handedly killed the Seven Shinobi Swordsmen and their leader, the Heir of the Serpent Lord (throwing mystics across the world into confusion, since according to prophecy the Heir had been supposed to slay the Lightbringer in the Battle of the End and thereby cast the world into darkness), had saved Captain Kakashi's life through an epic dance-off with the God of Death, and had seduced the Queen of Wave (at this point Hinata had felt inexplicably compelled to run to the nearest atlas, which informed her that Wave hadn't been a monarchy for three hundred years). At least half of them had probably been started by Naruto himself, but this only made her wonder more about the other half.

Captain Kakashi wasn't helping, as for reasons best known to himself he'd chosen to answer all queries with a completely deadpan "All rumours regarding Uzumaki Naruto are one hundred percent true; all of them. And yes, he is the reincarnation of the First Hokage and Uchiha Madara and General Chaos."

Naruto was still looking at her, still expecting something. She couldn't rely on her assumptions, that much was clear. But how else was she going to work this out, with as little information as she possessed?

She took a deep breath. No, they'd been over this. Don't propose solutions until you'd thought about it for five clock minutes (which was an excruciatingly long time to have to sit still while Naruto watched you, not that he seemed to realise).

But once she'd started looking for things that weren't solutions, it didn't take long for her to think of the question she should have asked from the beginning. Naruto was a genius, and some of those rumours might even be true, but he was still only human. How had he figured out what the incomplete Substitution Technique was good for?

-o-

Around the same time, Sasuke was wandering the streets of Leaf, meditating on the ubiquity of weakness and betrayal, and how it had come to be that he alone was aware of the true, twisted nature of the world. He never reached an answer, however, as his senses suddenly alerted him to something out of place.

The girl walking a few metres in front of him was wearing a folded battle fan on her back. Not a hand fan, either, but one of the full-sized weapons of war that had not been seen in Leaf for many decades, after Uchiha Madara's specialisation in that weapon had linked it to vanity and arrogance in the public mind. Of course, Madara had only been following an earlier tradition: the Uchiha clan symbol had, for all of recorded history, been the Fan That Feeds the Fire, and indeed "Uchiha" itself was a corruption of an ancient word for "fan". As such, Sasuke made it a point of pride to know all there was to be known about that particular weapon. This specific fan type would not be particularly effective in the Fire Country, where attempts to gather great winds were impeded by the endless forest, but in the flat deserts of the neighbouring Wind Country (where Leaf's ally Hidden Sand was based), one who mastered it would be lethal indeed.

His curiosity piqued, Sasuke looked more carefully. The girl, a blonde, was the leftmost of a party of three, each carrying something on their back. In the middle was a shorter, red-headed boy with an oversized gourd, while on the right, a tall shape of indeterminate gender (from the back, at least) wore a full-body black suit and carried a strange-looking cocoon of bandages. Their equipment and their body language clearly said "ninja with a purpose"; but what would Hidden Sand be doing here?

Not that he was going to strike up any sort of conversation with them, of course. That was the kind of thing Naruto would do, inflicting his presence on others with no sense of when he was or wasn't wanted. No, Sasuke was just going to—

Slam.

Some kid apparently hadn't been looking where he was going, and had charged straight past Sasuke and into the red-haired boy in the middle of the ninja group. The sequence of events that followed was surreal.

The redhead didn't seem at all offended. Instead, he turned around and looked down at the kid (Sasuke now recognised him as the Hokage's loser grandson, Konohamaru) with a gentle, contemplative expression, as if trying to decide what to teach his little brother today. But whatever Sasuke's feelings at the sight, they were betrayed when he noticed that the foreigner had a prominent red tattoo in the top left of his forehead: "purpose" in traditional characters. A real ninja didn't need to write reminders of his importance on his face for everyone to see, and such posturing revealed the boy's apparent kindness to be nothing more than a mask for condescension.

The look on the girl's face, initially neutral and distant, quickly turned to anxiety. "Gaara, no!" she hissed, urgently but quietly enough that a lesser ninja wouldn't have been able to hear it from this distance.

Gaara gave her what could best be described as a reproachful look, and didn't keep his voice down at all. "Temari, I haven't killed anyone in twenty-four days. You know what happens if I go too long without killing."

The joke—obvious as such from the fact that Sasuke couldn't sense even a whisper of bloodlust—was in poor taste, and only confirmed Sasuke's dislike of the little poser.

But Temari's whole body seemed to tense up, as though she'd suddenly found herself in a life-or-death situation. She glanced briefly at Sasuke, as if not knowing what to do with him, then looked back to Gaara. "Remember what Baki-sensei said," she whispered more softly (as if that could help against the lip-reading prowess of the Uchiha). "No killing anyone until after the second stage of the Chūnin Exam."

The third figure, a boy who might have been all right but for the ugly purple war paint on his face, finally weighed in with a nervous mutter. "Listen to your sister, Gaara. Listen to Temari. Please listen to Temari. She knows what's best for you."

Gaara looked back down at Konohamaru, who seemed to be on the verge of tears. He tilted his head slightly.

For an instant, Sasuke's vision blurred, and instead of Konohamaru he saw Inari lying on the ground, his hand raised in a feeble block that wouldn't ward off a punch from a drunken civilian, never mind an attack from a ninja. It was impossible, of course, and Inari was safely in the Country of the Wave. But by the time Sasuke had reminded himself of this, he was somehow already standing in front of Gaara, his body weight shifted very nearly into a combat stance, and his Sharingan active in as explicit a display of threat as he could project.

After a very, very long second during which Gaara regarded both of them with a calculating expression, the redhead suddenly smiled. Ignoring Sasuke, he glanced sideways at Temari, and then gave Konohamaru a sort of conspiratory shrug, as if to say, "See the kind of thing I have to deal with?"

"I apologise," he said, with a light bow that seemed to have no trace of mockery. "I promise I will kill you after the second stage of the Chūnin Exam, so please wait until then."

And before Sasuke or Konohamaru could make sense of what had just happened, the three were gone.

-o-

Hinata collated her impossible experimental results with a frown. Within the field of Naruto's chakra in the middle of the clearing, the Substitution Technique did not work (in either direction). This despite the fact that the Substitution Technique was not a thing that could be blocked. There was no known technique that prevented a person who was following all the rules—the Rule of Stability, the Rule of Consent, the Rule of Conservation of Space, the various rules relating to size and shape and correct visualisation etc.—from shifting herself or an object into phase space, or from shifting back. It was one of the reasons why space-time techniques were so coveted in spite of their high difficulty.

It only got worse from there. The Clone Technique didn't work either. While there were techniques, very advanced ones, that could destroy clones as fast as they were created, she knew of none that could block the process so completely that she wasn't even allowed to spend the chakra. She was able to walk pre-made clones in from outside the field with no harm done, but they were then subject to the same limitations as she was. This had in fact been the first thing she learned, in accordance with Naruto's Law of Experimentation Number One: Get a Clone to Do It First.

That left only one basic technique that Naruto would have known when experimenting himself.

But the Transformation Technique fared no better. Hinata was good at the Transformation Technique, it being a way of temporarily becoming someone or something else, and tried it every which way. She even tried transforming into the Perfectly Generic Object, an Academy training aid specially designed to be an ideal target for transformation, and useless for absolutely every other purpose. But her attempts went nowhere.

So that left her with exactly one more thing she could try.

Hinata walked out of the field, and turned to Naruto. "I'm going to use the advanced version of the Transformation Technique to turn into... let's say Sakura, and walk into the field and see what happens."

Naruto had drilled her very thoroughly in certain elements of ninjutsu experimentation, and one of these was that if you were experimenting on how your techniques interacted with someone else's, you cleared every single experiment with them first. And if ever she felt tempted to ignore the safety procedures Naruto had taught her, there was always the memory of the Hair-Raising Incident.

"Don't," Naruto said quickly. "You'd get the same results as for the other techniques—can't activate, can't dispel once activated, otherwise working as normal. But don't actually do this one."

"Why shouldn't I..." Hinata cut herself off. She was still in mid-test, so she had to try to work this out herself.

Hinata thought the process through step by step. The Transformation Technique always began by shifting your real body into phase space. At the same time, you applied all your concentration to shaping the chakra you left behind into a custom anchor, possessing the properties of a physical object but also allowing limited sensory input. Only in the case of the advanced version, that physical object was a remote-controlled clone of sorts, shaped like the person you wanted to imitate. There were a number of limitations—for example, it took a lot of finesse to be able to use ninjutsu through a clone whose chakra system only partially resembled a human one. Otherwise, as Kurenai-sensei had explained, any sensible shinobi would be Transformed at all times during missions, to prevent enemies from guessing their powers from reputation (or even make them guess wrongly by disguising themselves as other famous shinobi), or to confuse opponents during combat in any number of ways, or to commit hostile acts while making accurate retaliation impossible.

The good thing about transforming into another person, on the other hand, was that you avoided the greatest danger of the Transformation Technique—that of transforming into an object smaller than yourself, only to become trapped in a confined space and find that you couldn't transform back. The Rule of Conservation of Space forbade objects to emerge from phase space if there was no room for them to do so, meaning that your real body could be trapped forever unless somebody brought your anchor out into a more open area.

That in itself was horrifying enough, but somebody could then destroy your anchor, triggering the Rule of Automatic Return. The Rule of Automatic Return prevented you from losing your connection to the real world and thereby being stuck in phase space forever, pulling you out the instant that connection was destroyed—but if it removed you from phase space, only for the Rule of Conservation of Space to leave you with nowhere to go… No one knew what happened if two rules directly conflicted like that, and that was partly because no one had ever experienced it and come back to tell the tale. (And since there was such a thing as going insane from shadow clone feedback, that avenue of investigation was deemed firmly closed as well.)

Hinata had nearly walked into an area where the Transformation Technique was blocked. Suppose some accident had destroyed her clone form, and Naruto's Dimensional Anchor prevented the Transformation Technique from bringing back her real body. She'd be... just gone, somewhere, or nowhere, or everywhere, and no one would ever know what happened to her, and she might not even be dead but she would probably wish she was. She could feel the blood draining from her face.

"Relax," Naruto told her, slowly, gently, evenly. "You're OK. You're safe. Everything is all right. This is why we always check first."

Hinata nodded weakly, and took the time to get her breathing under control. But it was an axiom of the Academy, and certainly of Hyūga Hiashi, and probably of Kurenai-sensei too though it hadn't come up yet, that near-death wasn't an excuse to slack off training. Hinata had to get back to work.

It clearly wasn't as simple as Naruto blocking her from shifting her body to or from phase space, since that wouldn't block the Clone Technique. Nor was it about blocking chakra emission (she'd used the Gentle Fist to check, aware that she was sort of arguably cheating by using a technique Naruto hadn't had access to). What principles did all three techniques have in common that he could interfere with? It wasn't the Rule of Conservation of Space, since there was plenty of space and Naruto's neutral chakra should have no impact on that. It wasn't the Rule of Stability, since she'd tried using the Substitution Technique on an ordinary log and failed. It wasn't the Rule of Consent, since she wasn't targeting another living being...

Hinata's mouth dropped open for the second time that day. Techniques didn't define a living being by form, they defined it by presence of chakra.

Chakra was intelligent. It knew its master and rejected all others unless told otherwise. It was why you couldn't use the Substitution Technique on another living creature unless it mentally consented or was chakra-drained virtually to the point of death. It was why you couldn't get in range of an enemy and then create a clone inside them pre-transformed into something small and deadly. It was why medical ninja could shape their chakra into scalpels for self-defence, but couldn't invert conventional healing techniques to serve as one-hit-kill touch weapons.

"You've made this entire area an extension of your body, and now nobody but you can use any technique that involves the Rule of Consent," Hinata told him with awe.

Naruto beamed. "Yep. And that covers a whole bunch of stuff—summoning techniques, for example. There are exceptions, though, like the Fourth Hokage's Flying Thunder God Technique, and I've already figured out some hard counters someone could use if they knew the right ninjutsu. So I'll be keeping this one a secret until I really need it."

Hinata didn't say anything. At this stage, it went without saying that she would keep Naruto's secrets, just as he would keep hers (at least once she had some worth keeping).

Then, out of nowhere, Naruto's expression turned melancholy. "Hinata, you know how this technique works now. Remember it if you..." he hesitated. "If you ever need to kill somebody who attacks with hordes of transforming clones."

Hinata gave him a puzzled look, to which he did not respond.

"Anyway, that was only meant to be a demonstration of why you shouldn't give up just because a technique doesn't work the way it's supposed to," Naruto said in slightly too cheerful a voice. "And I know I've eaten way too far into our normal training time, and I need to be at the Foreigners' Cemetery in an hour and a half, so how about we crank our sparring up to double pace?"

Hinata gladly obliged. She had a lot to think about, but... later. All later. For now, there was Naruto, and there was training, and she let that fill her whole world while she could.