A/N: I'm not entirely sure about the limits of the ratings, so just to be safe: heads up, there is a paragraph close to the end that might be pushing the T rating a bit!

One final lesson

With an annoyed groan, Gatō put the last stack of money into his safe and slammed the door shut. The amount of cash he kept in there was small compared to his assets in total, but it was a notable sum that wanted to be taken care of. After all, one should always have a bit of liquidity on hand. And he did enjoy doing it in principle. But unfortunately, sorting through the banknotes, organizing them in neat stacks, and recounting it all to make sure his books were correct was an absolute pain when you only had one arm available to achieve that. He threw an angry glance and the cast that went all the way down to the fingertips of his left hand. He would get back at that stupid brat for breaking his arm. And the tall guy as well. He had spent a fortune hiring him, only to then see the oh-so-mighty 'Demon of the Hidden Mist' carried back beaten and unconscious by that boy that accompanied him. At least he had managed to stop that stupid bridge builder from entering the Land of Waves, but he was still alive. And now, he had gotten a report that the old man was on the move again, while Zabuza was still recovering. How the hell did that guy even have enough money to hire another escort? But he couldn't have much left. In that sense, that 'Demon' getting injured worked out well in the long run. In his weakened state, even a cheap escort might be enough to power him out, and then he could have his men kill him. The bridge builder would dead, and he saved a lot of money. He would've loved to finish him right now, but he couldn't risk it while that guy was still alive.

From downstairs, he could suddenly hear loud noises. A fight? Did one of his mercenaries get drunk again? But it was lasting a bit too long for that. Rolling his eyes, he grabbed his cane and went to check on the commotion, the two goons that had been standing guard at his door following him. Halfway there, a gross smell suddenly assaulted his nose.

"Bah, what's that?!"

"Careful, boss," one of the two mercenaries warned. "That's the smell of blood."

"... you open the door."

The man nodded, drew his weapon, and opened the door to the hall, just in time to see another one of the mercenaries being bisected. The hallway was filled with cut-up corpses, and in the middle of the massacre stood Zabuza. His left arm was still bandaged, but otherwise, he seemed to have recovered. The brat that looked like a girl stood close to a wall.

"W-w-what the hell are you doing?!" Gatō screamed, and the two men at his side pointed their weapons at Zabuza.

"You should put that away," the former Mist Ninja warned the goon. "Or else you might end up like your colleagues."

"W-we had a contract!" Gatō took the word again, both appalled and furious. The bandaged man looked at him, making the magnate flinch.

"Contract? Those clowns were never mentioned in our contract. One of them was being annoying so I made him shut up. Then the rest reacted stupidly to that. Hardly my fault if they are suicidal. Besides, they are much more useful like that anyway. There aren't many animals with as much iron in their blood as humans."

To underline his point, Zabuza raised his blade, and Gatō could see the blood on it got absorbed into the metal, causing it to… regenerate? The formally broken cleaver was almost entirely whole again. The magnate gulped, but he had to take back control of the situation. Who cared if ten replaceable goons were dead? He had many more.

"F-fine. Anyway, your target is on the move again. You better not fail me this time!"

"I won't. That girlie will not catch me off-guard again."

Girlie?

"I don't know if it's the same guys again, and I don't care for any personal vendetta of yours. Just make sure the dies this time!"

"I've been lying around for too long anyway."

And with that, the two ninja went on their way. Gatō watched them leave from the window until he could no longer see them again. With them gone, a good portion of the tension in his body finally left and he went back to his office. He really should prepare to get rid of the guy.

But as soon as he was upstairs, the next surprise was already waiting for him. In his chair, feet on the desk, sat somebody. It was a man wearing a black cloak with red clouds on it, and a headband similar to Zabuza's, except his Mist insignia seemed to be crossed out. Had Zabuza called in another of his Missing-nin? But why hadn't he said anything? And why would this guy be in his office? Also, why was he twirling a stack of banknotes around his fingers?

With a side glance, Gatō noticed that his safe was missing his upper part as if it had gotten… cut open.

"Heya!" the man greeted him and tossed the money away. "Sorry about your purse, I thought you maybe had something interesting stored there. But I guess he wouldn't employ someone that stupid. You probably burn your orders once you read them, huh? Only makes sense, after all."

What the hell was that guy blabbing about?

"Who the hell are you?!" Gatō asked from behind his two guards.

"The name's Kōzui," the man said, seemingly not caring about the swords pointed at him. "Can you imagine my surprise when I heard of this little plot you're pulling here? I knew Yagura was a bastard, but I didn't expect him to be this sneaky."

"What the hell are you talking about?!"

"Still wanna play dumb? Well, fine by me, orders are orders after all. I know that too well. Although me coming here wasn't exactly the plan. But Kakuzu can handle himself. And I couldn't just pass up this chance."

Suddenly, the two men flanking Gatō collapsed to the ground. Appalled, he saw a shuriken stuck in each of their heads. He hadn't even seen the guy throw them.

"I mean, don't get me wrong. I'm pissed at Zabuza that he's still working for the guy, I honestly expected more from him. But I didn't want to waste any time with him and risk you getting away. Sure, you weren't technically part of the mission, and I know you're just a figurehead. You'll still make a great messenger, though. Or message, I guess. I mean, can you imagine Yagura's face when I send him your head? When he learns that all his efforts were for nothing, that whatever he wants from this tiny country, he can't have it? Too bad I won't see it. But hey, look at the bright side, if he learns that you failed, he would've killed you anyway, and much slower than I will."

Suddenly, the man no longer sat in the chair and was instead right in front of him. Before Gatō had any chance to react, the blade of his sword glid through his neck. In his last moments of consciousness, as he could see his headless body fall to the ground, he still had no clue what this guy had been rambling about. This wasn't supposed to happen! The Land of Waves was simply meant to be a secure base for his more obscure businesses! And he had planned for everything! Just where had he gone wrong?

Two months later

Kurenai watched Kiba raise his hand, giving the team the command to stop. The three Genin came to a halt with Kurenai standing a few steps behind them. She had finally recovered fully, and after a week of build-up exercises, she felt more or less recovered. Until then, she had only been able to oversee the kids while they trained or did D-rank missions, but considering how the last C-rank went, she didn't want to risk something going wrong without her being a hundred percent sure that she would be able to diffuse the situation if necessary.

But that didn't mean the time she had needed to recover had been spend unproductive. And that was why she had decided that for this mission, she would let them take the reins and only interfere if necessary. The task was to locate and bust a small bandit camp close to the border to the Land of Rivers, catching them alive if possible.

Kiba had immediately taken on the role of team leader, but that didn't surprise her. And so far, he hadn't done a bad job. He was still charismatic, but notably less hot-headed than he used to be, and seemed to also respect that his teammates simply had a different character rather than him rather than insulting them for their demeanor.

Earlier, Kiba had Shino locate the camp with his insects, then had them wait until nightfall to approach, while continuously making sure that he and Akamaru would sniff out any potential scouts that could notice them. So far there hadn't been any.

"Okay, we now should be about half a kilometer away. Hinata, can you see how many there are?"

The girl nodded and activated her Byakugan.

"It's indeed just a small camp," she spoke after being quiet for a few seconds. "A couple of tents and a simple fence to keep animals away. I count six people sleeping and two standing guard."

Hinata's change during the past months had been the most notable. Her stutter was completely gone when she was focused, and only occasionally appeared in normal dialogue. She also stood more upright instead of being hunched over all the time and seemed to have started growing out her hair. She was still a shy and quiet girl, but she no longer was a nervous wreck. She also had her jacket open now, reminding Kurnai a bit of her friend Anko – which was funny because character-wise, Anko was the exact opposite of Hinata. Though a clear difference in style between the two was obviously the fact that Hinata wore a black shirt and pants underneath, not just mesh armor on blank skin.

There was just one tiny twinge in her mind that she couldn't ignore. She had always tried to be a good sensei and provide guidance, both before and after her hospital visit. But it was very clear that the changes in the kids had been jumpstarted during said visit. In other words, the only real options were either Asuma or Tanya. Of course, the top priority was to achieve the best outcome for the three kids. She had a duty and responsibility again, they weren't just tools to show off her own skill. But it was hard to ignore that whatever she achieved from here on out was an addition to a foundation built by someone else.

"Alright, let's go! We'll quietly take out the guards, and then the rest will be easy."

Reaching the camp unseen was no challenge thanks to the forest providing cover. Shino started to prepare a swarm of his bugs while Kiba went down on all fours.

'Gijū Ninpō: Shikyaku no Jutsu!' [Imitation Beast Ninja Art: Four Legs Jutsu]

The attack began. Shino's bugs swarmed the first guard and filled his mouth to prevent him from screaming. At the same time, Kiba – whose jutsu had made him take on some more animalistic traits – charged at the other guy. He didn't care if he was seen since he knew he would reach his target before he could react. And he was right, pouncing on the second guard and getting him into a chokehold. But before he lost consciousness, he managed to hit the bell next to him. It was just once, but it was enough to wake the others. Realizing this, Shino and Hinata dropped their stealth and charged the camp as well. Kiba and Akamaru had already managed to knock out another guy. The rest came crawling out of their tents, but groggy from their interrupted sleep they weren't serious opponents. Shino, with no intention of hiding behind his bugs, attacked together with them, using some as a diversion to blindside one of the bandits with a kick to the head while the rest swarmed another, eating away his chakra until he collapsed. Which didn't take long considering he wasn't a ninja. At the same time, Hinata got attacked by three at once. Rather than preventing getting surrounded, she simply let them come before avoiding all of their attacks in one fluid motion and hitting them with her flat palms so quickly that wisps of chakra could be seen like a trail that followed her movements. That move was new.

The entire assault didn't even take two minutes, and shortly after, all eight bandits lay tied and unconscious on the ground.

"Not bad in total," Kurenai complimented her students, "but you had a few hiccups. For example, had you waited a bit longer, the guy Kiba attacked would've walked further and hadn't been close enough to the bell to ring it."

"Yes, sensei."

"By the way, what was that stance you used there at the end, Hinata? Didn't look like your usual Gentle Fist."

"It wasn't. I've been e-experimenting a bit lately."

"Then you came up with it yourself?" That was certainly unexpected. To think that the girl who had apparently always struggled to live up to her stuck-up clan's satisfaction would dare to vary that ages-old fighting style.

"Yes, T-Tanya-sensei said to master a fighting style, I can't just copy it, I have to make it my own. She said that was the second reason my movements felt uncomfortable, I was too d-desperately trying to imitate the exact stances that I couldn't adapt it to my own capabilities. She also said something about an age-old dispute between the philosophy of becoming your teacher versus f-freeing yourself from your teacher, but I didn't really understand what that had to do with east and west."

Tanya. Of course it was you. Once again, you surpassed me without even trying, didn't you? …no, I have to think about Hinata for now, I doubt this is something she can talk about with her family. They'd probably see it as a violation of their oh-so-sacred traditions and shun her even more.

"I might not be all too familiar with the Gentle Fist style, but I'll gladly look at what you came up with. Maybe we can work something out together."

"Thank you, Kurenai-sensei!"

Huh, I can't recall ever seeing her this happy. Still, the fact that she didn't come to me with this from the start means I'm still lacking as a sensei. At least she didn't outright go to Tanya instead… no, stop it, this isn't about her! Although, now that I think about it, I haven't seen Tanya and her team for quite some time. I wonder what they're doing.

Sakura closed her eyes and spread her arms, feeling the wind rushing by. On her first flight, she had simply been luggage, but since she had gotten closer to Itoshīga, it felt closer to actually flying rather than just being carried. And it felt great! She could fully understand why Tanya loved it so much – even if the young Jōnin would never admit it. But the faint smile she subconsciously displayed whenever she was soaring through the air was unmissable up close.

The yellow-fuzzed moth was much less… regal than her sisters, which made her much easier to talk to. She wouldn't say that she had formed a bond or anything like that with Itoshīga, but it felt much more like working together than just being carried. Over the course of the last two months, the moth had frequently brought her to different locations Tanya had used for her training. Most of the time she used the local, sometimes outright hazardous environment to teach her one thing and always simultaneously something else, giving her not a moment of rest. To call the past two months torture would have been an understatement. More than once had Sakura wanted nothing more than to simply quit, occasionally to the point that she had even started crying. Not that Tanya had cared. But each time she had managed to remind herself of her goal, what - and who - she was enduring all of this for. And in the end, she managed to power through.

In the forest surrounding the Hidden Leaf Village, they landed and Tanya dismissed the two moths. Readying to meet the two boys again for the first time in two months, Sakura used a nearby puddle to take a quick look at herself. She certainly had changed. The most obvious thing was her clothes. The first damages on her original clothing had simply been ignored as they were alone all the time anyway, but it eventually reached the point where they simply didn't function as clothes anymore. Too far away from any chance to buy new ones, Tanya had summoned some larvae to make a replacement from their silk (and mumbled something about wishing the Moth Queen had more understanding for capitalism). Sakura had simply asked for something similar to her old stuff, but the moth children had taken some creative liberties.

Her black undershorts were more or less the same. Her dress on the other hand now had a slightly darker shade of red and was a bit longer, with high slits to minimize any impact on her freedom of movement. The torso portion now had some padding, which together with the mesh armor Tanya had given her to wear underneath provided a decent amount of protection. There were also some hidden pockets that allowed her to carry some ninja tools in addition to her normal belt satchel and leg sheath. The formerly white outlines of her dress were now silver and her back, rather than a plain circle, now sported an emblem showing a stylized wing.

She took a deep breath and looked at the village gates in the distance. At face value, two months weren't all that long. But to Sakura, it felt like she hadn't seen the village for an eternity.

Meanwhile, Tanya suddenly groaned and pressed her hands at her temples.

"Tanya-sensei! Are you alright?" Sakura asked startled, almost activating a Mystical Palm Jutsu on reflex.

"Yes, yes. I'm just getting two times two months' worth of memories, that's a bit taxing."

Getting upright again, she pulled out two scrolls, opened them, and threw them to the ground. Both had the same complex sealing formula written on them, each centered around a large 'person' kanji. It didn't take long until the scrolls started to convulse, the center rising like it got pulled up. Sakura could feel a large amount of stored chakra getting released as the seals activated.

The chakra sense was about the last thing Sakura had expected to learn. It was a skill that seemed to be purely associated with Sensor-nin, but Tanya begged to differ. Due to Sakura's excellent chakra control, the young Jōnin had been adamant that she should at least learn a rudimentary sensor skill, emphasizing that it could prove to be a great asset for their team.

In a puff of smoke, Sasuke appeared from one of the scrolls. Optically, he looked almost the same as at the start of the training, except for slightly longer hair that, as always, looked like there had been an attempt to make it look decent. From the edge of his collar, she could see that he was now also wearing mesh armor underneath. On a second glance, she also noticed that his shirt was now black. So she wasn't the only one who had gotten new clothes, although his had notably less creative liberties. But his presence had changed drastically. He had never been a slouch, but now, he practically oozed pure confidence.

From the other scroll appeared… a girl? Her long, blonde hair was tied to pigtails, her smooth skin interrupted by whisker-like markings on her cheeks- wait.

"Naruto?!"

"Heya, Sakura!" the girl greeted cheerfully. "Woah, you look different!"

"Me?! What about you?!"

"What about me? Oh, whoops!"

Another puff of smoke, and the Naruto she knew was there again. He also wasn't much different on the outside, his spiky hair just being slightly longer. But one glance was still enough to tell he had changed as well.

"Didn't notice I was still transformed, hehe. Did I look cute?"

"Idiot," Sasuke commented, but unlike before, he sounded more amused than annoyed.

"Bah, you're just embarrassed because I made you blush, admit it!"

"Suuuure," the black-haired boy said with a voice dripping with sarcasm.

Bizarrely, their interaction felt both the same and different than before. They were clearly still the same people, but… well, calling it more mature would've been the wrong term, but it felt less like childish bickering. Of course, if her own experiences were anything to go by, both of them had only found this version of themselves shortly before coming here. She herself definitely had been an absolute mess from the training before she reached that point.

"So anyway, Sakura, what's with the Genjutsu?"

The casualness with which Naruto asked the question caught her off-guard. He hadn't even asked if she had an illusion active, that much seemed to be a given. And, well, he was right. She was masking her bodily odor. The fact that Tanya had trained her to see such things as trivial when on duty didn't mean she had to make a bad impression when not. At least he had just noticed it and didn't break it.

"Why the confused face?" her sensei asked the pinkette. "Did you forget you're not the only one I trained?"

"Yup! I even got special training!" the blonde boy proclaimed proudful.

"You mean you needed special training," Tanya corrected. "But anyway, all of you did well. I'll be honest, I had some doubts, but each of you met or exceeded my expectations."

"Then you will recommend us now, right?" Naruto asked with a cocky grin.

"I will not."

The silence following her immediate answer was deafening and weight so heavily that the three Genin almost felt like they had no air.

"What… what do you mean?! You said you'd recommend us if we're strong enough! And just now you said we exceeded your expectation!"

"I thought I told you to listen closely. I never said anything about strength, I said I'll recommend you if I think you are ready for it. In terms of pure ability, all of you are easily Chūnin material now. But that and being ready are two different things. Which is why the training isn't over yet. I booked training field 6 for today, get there and familiarize yourself with each other's abilities. We'll meet at the Hokage Villa at 5 pm, I have one more lesson for you!"

Punctual on the minute, the three arrived at the meeting spot. With a nod, I guided them to follow me, curious looks on their faces. I assumed they were all wondering what the promised 'final lesson' would look like. And I knew for a fact they had no idea what was coming for them. I admit, what I was planning was a bit much, both for regular soldiers and definitely for children. But this fucked up world required fucked up methods. While I didn't care much for the three on a purely personal level, I still absolutely hated the concept of sending kids so young into the battlefield. The last four months primarily served the goal that, starting tomorrow, the Hokage would be impressed by my skill as a teacher, mentor, and leader. But today… today I would tear off the band-aid that could get the three killed if ignored. It had to be done. Should they become Chūnin, and they definitely had good chances, then the team would be dissolved and I would no longer be their sensei. In other words, this was my last chance.

We reached an unassuming building with no windows and entered without knocking. The people walking about ignored me, already knowing I would be coming. The three kids carefully looked around, appearing to be slightly uncomfortable in the claustrophobic environment. In a plain hallway illuminated with nothing but dim electric light, I knocked on a door.

"Yes?" a rough voice answered from the other side and I entered, the kids following. Inside, we were greeted by a man with a face so scarred his age was difficult to estimate. A bandana with the Leaf emblem covered his head, his body was clad in a long, black jacket, and his hands were covered in black gloves. His desk was filled with loads of paperwork.

"Tanya," he greeted me with a nod. "Sorry, I still got some stuff to prepare for tomorrow. But the room is ready, just go downstairs and… do you still remember how to get to your special room?"

"Yes."

"Good, then from there it's two doors to the left. Just tell me when you're done so I can send someone to clean."

"I will. Thank you, Ibiki."

"No big deal."

Following his instructions, I quickly found the room he was referring to when he said 'my special room'. I wondered how often they had used it since. It had certainly proven to be effective back then, but I hadn't been here again after I had won my bet.

"What is this place?" Naruto asked much later than I had expected.

"This is the T&I Department," I explained. "A part of our work not many shinobi get to see."

"T&I?"

"Torture and interrogation," Sasuke translated before I could. But I had already anticipated that of the three, he would be the one who would have at least heard of this place.

"Correct. Although I'm honestly not sure why it is called torture and interrogation…" I opened to door Ibiki had described. "… since down here, these two words are more or less synonymous."

The kids let out a shocked gasp. Inside the room, tied to a pole each, stood three people dressed in rags. Although hung might have been a more apt description, as their chains were the only things keeping them upright, their bodies clearly missing the strength to do so. All three were blindfolded and their mouths hung open weakly, but the way they breathed showed that they were still conscious.

The one on the left was a woman who had her head shaven cleanly, showing the multiple holes that had been drilled in her skull. Her broken fingers had turned purple and were bending at unnatural angles, and the dried streams of blood coming from under her toenails didn't leave much to the imagination of what had been done there. The one in the middle, a man, was missing a good portion of his teeth, and his exposed torso was riddled with burn marks. The last one, another man but older than the first, didn't seem as badly injured at face value. But the clearly self-inflicted wounds told me they did indeed still use 'my special room'.

"Who… who are these people?" Naruto eventually asked with a shaky voice.

"Enemies," I simply replied. "Just because we're not at war doesn't mean there is total peace. There are those who wish to steal delicate secrets or weaken us from within. Those might not be open battles, but dangerous threats that need to be dealt with nonetheless. But unlike a bandit trying to ambush you, those people can't just be fought and be done with. To properly deal with the threat, we need to know it. But of course, they don't just tell us… unless they get incentivized. And that is what the T&I Department is for."

I crossed my arms and turned to face the three kids properly.

"There are a few things learned from this. Can you tell me why I brought you down here?"

It was quiet for a while. In the end, Sakura was the one who spoke first.

"As a reminder," she said. "Shinobi work can be gruesome. For the greater good of the village, we may have to do terrible things."

"Correct. What else?"

"A warning," Sasuke added. "Should we get caught on a high-ranking mission, this could be what awaits us."

I nodded and looked at Naruto next, but the blonde just showed a blank gaze.

"Then let me tell you," I broke the silence again. "These three told us what they know. But that doesn't mean we can set them free. The knowledge they acquired is too dangerous, and their deeds must have consequences. The only peace they can hope for is death."

I tossed three kunai to the kids, each catching one with little effort. Their brains, however, took slightly longer to catch up.

"W-wait… y-you don't want us to…" Sakura finally stammered.

"You must learn to kill," I stated sternly. "Not just in the heat of battle as a consequence of a too-strong attack, I'm talking about the conscious decision to kill. Just like each of your blades and every jutsu in your arsenal, so is the act of killing itself a tool, one that must be utilized properly. You shouldn't grow to enjoy it. You don't even have to get used to it, even though it would be better. But either way, you must be able to recognize when it is necessary, and then do so without hesitation. That is my final lesson to you."

A/N: And that is it for the preparation arc. I know some of you wanted the training montage to go on longer, but any more would've spoiled the fun of them revealing their skills in the exams.

End of an arc also means another snipped from Tanya's past. I've read all of your feedback on the last one, both positive and negative, and I'll slightly change the way I approach the following ones. But I still think they can provide important context, which is why I don't leave them out or put them in a separate story.