A.N.: I may not reply to all reviews but I do take into account every single one of them.


What Doesn't Kill You

Chapter Eight

[Patient: able to accept or tolerate delays, problems or suffering without becoming annoyed or anxious.]


One of the advantages of being a med-nin was that one was able to control the amount of damage one dealt to a target. Maximizing the intensity of pain inflicted while avoiding permanent injuries, and he could do it as many times as he wanted by healing and inflicting again. Which was why Kabuto was one of Danzo's favorite instructors.

It had taken an unusually long amount of time to break Aoi Momoru. Normally, children of that age were much easier - after two weeks or so of mental and physical abuse, exhaustion, food deprivation and loneliness they were forced to shut out their emotions and follow orders without hesitation. Loyalty to Danzo became their religion. The initial phase of the Root program was designed to instill total obedience and erase identity, creating an unconditional follower which could be shaped into a soldier in the following years of training.

After two months Kabuto still wasn't sure where he was at with Aoi. Most of the time she was meek, blank and obedient, as she should be. But there were instances in which her eyes shifted away from him in a dismissive manner, or times when she made what could be mistaken for a small challenging gesture. Kabuto didn't know if he was imagining it because when he looked twice she had the indifferent expression on her face again and answered whatever order he gave her with the same bland, "Yes, Kabuto-senpai."

But Danzo was growing impatient and after an interview with her, the Root leader deemed her ready to move on to the next phase of the program, despite Kabuto's reservations. She was no longer only Kabuto's responsibility. He still taught her medical ninjutsu, but she'd started being taught proper ninja skills with the other children. The physical abuse of the first phase was toned down and they weren't denied food and rest when they needed it - though insubordination still warranted harsh punishments. Privileges were also given if one of the children performed exceptionally well.

There were only five children in phase two at the moment, including Aoi, and only one of them was of the same age as her, the others being at least two or three years older. It didn't matter, because she caught up to their general level in just over a month.

Kabuto knew even he hadn't shown such rapid progress and it irked him.

Root being a division primarily focused on infiltration, the first techniques they were taught differed from what they'd have learnt at the Academy. How to conceal their chakra signature, how to use their age to gain information and the Transformation technique. "It's very hard to hide one's chakra while performing a jutsu. Most chunin-level ninja and above will be able to tell that the signature's off, especially if you transform into somebody they're familiar with. However, it's very useful for fooling civilians and hiding in crowds." Kabuto pushed up his glasses. "Well, go ahead. Transform into an unassuming civilian."

Most of them failed. It was understandable, since it was the first time they attempted the technique. Either they forgot bits of the transformation, or the jutsu flickered, superimposing both images, or the result was humanoid in shape but lacked detail.

Aoi Momoru's transformation was perfect. Kabuto found himself looking up at a young woman with straight, limp brown hair, green eyes and a slightly larger-than-average nose. She wore strange clothes, tighter than he was used to with a leather handbag hanging from one shoulder. She smirked down at him for a second before her expression turned back to its usual blankness.

The transformation was older than him by a few years. She was also taller than him. He didn't like it.

"Well, everyone, keep practicing. Aoi-san, why don't you start working on turning into inanimate objects?" A pity he couldn't hit her as often anymore. By the end of the session, the other small kid, the one who was drawing all the time, was the only one who'd managed a passable human transformation apart from her.

He took his revenge in the next specialized medical ninjutsu session. They were dissecting for the first time - and he knew from experience that, depending on how the demonstrator handled it, it could be quite traumatizing. But her reaction was woefully underwhelmed. She leaned over the torn open ribcage, crushed organs and dark blood and bits of bone mixed into one gory mess, and made a contemplative sound. "If you replace the blood with a fixing agent before opening it up, it's less messy."

Kabuto pushed up his glasses. Bits of intestine hung from his arm and the gesture accidentally smeared blood on his clothes. "Whatever."


Aoi looked at Sai (though she knew that wasn't his name now) and then at the older Root member who'd been teaching them that day. She had a bear mask with four holes for the eyes instead of two, which was downright creepy. "Well? Get ready."

Sai blinked and slid into a pose which looked suspiciously like a fighting stance. This was the first time Aoi had any kind of taijutsu training so, not knowing what to do, she just mimicked him. At the Academy they'd still been playing ball games and doing obstacle courses when she left, and for most of it she'd just found a quiet corner in the shade to nap. She didn't see the point of starting physical training so early, when their bodies still had to develop. Also, she was usually exhausted from the nocturnal studying.

Sai had been fairly easy to recognize. He was the only kid around her age and the only one whose skin was paler than hers. He didn't talk much, and she'd never seen him without his sketchpad nearby. His eyes were wider than they'd be when he was older, making him look decptively innocent. Really, even in a fighting stance he wasn't very threatening, with his chubby cheeks and small nose and -

"Begin!"

Aoi blinked at the ground her face was pressed against, having entirely missed whatever had put it there. Her arm was pinned painfully against her back and one of her legs was trapped underneath something heavy. As she blinked again something hit her in the back of the head and she saw stars.

"Enough," the Root agent said, and immediately whatever was holding her in place disappeared.

Aoi picked herself up, disoriented. Sai was standing a few meters away from her, back in his stance, as if he hadn't just crushed her into the ground like a worm. "Begin!"

This time she felt her ribs crack and she slammed against one of the walls of the room, all the air leaving her lungs in a whoosh. "Girl, we're going to keep doing this until you land a good hit on him." For a moment of panic Aoi was unable to get any air in her lungs again until it finally flowed, and she bent over, gasping. Yup, cracked rib. Fuck, Sai.

He came at her again. She didn't have time to do more than put her arms in front of her face as he methodically beat her down, punching and kicking and snapping every part of her that wasn't covered by her arms. There was more breaking and blood. Sai hit like a sledgehammer, and he targeted the joints and weaker areas. At some point Aoi lost track of it and simply curled up into a ball, waiting for it to be over.

Finally, the blows stopped. It felt like an eternity, though it probably wasn't more than a dozen seconds. "I've broken or dislocated her arms and legs. I doubt she'll be able to hit me now."

Aoi made a sound. She was in so much pain she didn't even know what she'd meant to say.

Sai looked back and added, "Should I kill her?"

The question sent a jolt through her, kill me? Fear pushed the pain back like a tidal wave. Numbing chakra crashed over her body, and she straightened one leg, kicking Sai's foot from under him. As he fell back towards her, already turning his head, she punched him across the face.

Her arm was so numb she didn't even feel the impact. It was like using a stick. She wasn't sure how hard she'd hit him but it must have been fairly hard, because Sai's head snapped to the side and he fell on her with an 'ooomph', before quickly rolling away.

The masked woman grabbed Sai's arm as he got up. "Alright, you both did well. Boy, go call Kabuto."

He shot her an indifferent look and scampered off.

Aoi was obscenely proud of having managed a punch on an eight-year-old. Bear woman didn't offer any further words of praise.

She maintained the numbing jutsu until Kabuto arrived. "Got yourself in quite a mess, huh?" he commented, in a suspiciously happy note, before leaning down and setting to work.

She concentrated, feeling how his foreign chakra wrapped around her cracked ribs and burst vessels and started threading them back together. "Kabuto-senpai."

"Yes?"

She licked her lips, sighing softly as her dislocated shoulder was eased back into place. "I read that the mystical palm technique works by stimulating the patient's cells to divide, grow and regenerate. But the Yin chakra med-nin use has no physical substance so it shouldn't be able to do that. So how does it work?"

Kabuto smiled. Aoi had long ago worked out how to play Kabuto. Nearly all his actions were centered around proving his superiority, whether that was physically or by showing off his superior medical knowledge. Kabuto enjoyed listening to the sound of his own voice and wouldn't object to teaching something as long as she didn't interrupt him. "What you do is mix the Yin chakra with the raw chakra passively produced by the patient's body, making a pseudo-refined chakra which you then re-inject in the damaged organ or tissue, directing its regeneration." He paused to push up his glasses, then started working on her other arm. "Though I wouldn't try it if I were you, it requires chakra control a level above what you can currently manage. There's a precursor technique called the Diagnostic palm which merely uses the Yin chakra to wrap around organs and assess damage. When you manage to not break the stone, you can try that."

Aoi thought for some time. Kabuto had finished and was about to walk out the door when she spoke. "But if I were healing myself, there would be no need to mix the Yin chakra in my hand with the raw chakra in the affected area. I could just make refined chakra the normal way, through the coils, and direct it into the affected area internally without use of my hands or anything. After all, my body won't reject my own physical chakra and it's much easier that way."

Kabuto paused at the door. "Ah, maybe," he said, and walked out.

Maybe, my ass, Aoi thought later, in her room. She was smiling up at the no-longer cut on her thumb, which she'd healed using normal refined chakra without any difficulty. There was no scar, either. He's just never thought of it before.

It wasn't something that any ninja could do. One still needed the theoretical knowledge of the organs they had to regenerate, which cells to stimulate and how much, and make sure the process didn't spiral out of control. But by eliminating the need to separate Yin and Yang components, self-healing required less chakra control and much less concentration, and was order of magnitudes faster.

It then occurred to her that later, Kabuto would fight Tsunade and Naruto using a jutsu that involved rapidly healing any area of his body that was damaged.

Huh. I didn't just give him the idea for it, did I?

Then she practiced moving around her chakra in her body, warming up various areas from her third toe to her left eyebrow. After a while she sat up and stared hard at the small white stone on the floor. She picked it up and injected a tiny bit of chakra into it.

Creating purely Yin chakra was a strange thing to do. You still had to pool the raw physical chakra in the coils but not let any of it into the chakra you sent back outwards. The stone's surface cracked at the top, but didn't break, and in a few seconds it was smooth again. Good enough.

She pocketed the stone, sent more chakra to her now empty hand, looked at it, breathed in, and placed it over her leg. If this went wrong the limbs were safer than the torso. Yin chakra had no physical substance and in theory couldn't damage her body, but it was still safer not to place it over a major tenketsu just in case.

The Diagnostic Palm was surprisingly easy. She could feel the place where skin met a layer of conjunctive tissue and then thick muscle. As she sent the chakra deeper she felt the stranger consistency of spongy bone, then bone marrow. She also came across the occasional major nerve or blood vessel and...

It's exactly like tree sap. The cells making up the chakra system are dead. She supposed it made sense, so that the chakra flow wasn't disrupted by the cells it traveled through, but still, it was exciting to learn that her body had somehow adopted a circulatory system similar to that of plants.

Aoi sighed and lay back down, thinking back to the fight with Sai. He was really good. She hadn't even been able to tell what limb he hit her with. The reality of the situation dawned on her again, that she was training to become a ninja and this was Root and at some point she'd be part of Danzo's coup to overthrow the Hokage.


Days passed. Maybe weeks. Maybe months. Sai still beat her up on a weekly basis but at least she had the numbing jutsu and the self-healing one to get through it. She let Kabuto heal her most of the time still, because she didn't want to give all her cards away yet and as much as she hated to admit it he was a better medic than her. He had years of Diagnostic Palm experience to draw on.

Her escape plan was still inapplicable.

She was relatively safe now, but Root was not a nice place to be in and she still fully intended to leave it. She hoped the Hokage wouldn't let Danzo have her forever, but if he had forgotten about her she knew she'd have to take matters into her own hands. She was waiting for the right moment. Unfortunately, information gathering was proving to be ridiculously difficult since everyone she came in contact with was stoic and tight-lipped and disappeared as soon as their business was done.

Someone knocked at her door. "Come in," she said without moving from her bed.

"I'd rather you came out here, Yellow-san," Sai's voice answered politely.

He was, perhaps, the only person who she could talk to on a more or less normal level. Him and one of the older children they trained with that called himself Shin. They knew more about the organization than she did and weren't so reluctant to share their knowledge. Shin in particular behaved in a relaxed and friendly manner when they were alone, though the emotionless mask slipped on when he dealt with an agent.

Aoi had been thinking on how to approach the topic of a breakout with him for a while. She had the feeling Shin was just as restless as she was, but didn't want to risk it until she knew more about him. If he tattled on her, it would be a disaster. Not to mention he seemed to have a soft spot for Sai and Sai shared none of his animosity towards Root. Sai was the perfect little soldier.

She pushed her thoughts aside and got up to open the door.

Sai was standing in the corridor, rocking back and forth on his heels, looking adorable with his short black hair and big eyes and not at all like a trained killer. "What do you want?"

"Danzo-sama said to bring you. We have a mission."

Aoi stared at him incredulously for a second. She'd only been here for a few months... How many months exactly? Anyway, it was way too short a time to already be assigned a mission. Sai seemed to sense her shock. "Don't worry, I've already been on one, and Danzo-sama said this one would be easier."

"I'm going with you?" she blurted.

He nodded. Aoi sighed in resignation and followed him down the corridor.

Great. Awesome. Hopefully it's outside this claustrophobic base and I'll be able to sneak some food. Hopefully it'll be a stupid D-rank about weeding fields or cleaning up rubbish. Hey, maybe I'll see the Hokage and ask him to get me out of here.

But no, of course it was an assassination mission. This was Root, after all.