Kagerō spent his days in a blur of routine and rain.
Morning always started the same: the dripping condensation from the rusting metal ceiling, the creaking wheels of the orphanage nurse's cart. He didn't know her name initially, only the smell she had. The smell of burnt tea leaves and antiseptic. It was only later he heard someone address her as Mera-san. Hard-faced, plain, with stern lines under her eyes that even the rain couldn't soften.
She wasn't nasty. But she wasn't kind either.
Just utilitarian.
Her hands were coarse from washing years' worth of linens and changing infants. When she picked up Kagerō to change him or feed him, it was with the same matter-of-fact approach one might take with military rations. Nothing wasteful. No softness lingered. Just what was necessary.
And curiously, Kagerō seemed to value that.
He wouldn't take pity. Pity became questions. Questions became noticed. And notice, in the environment of Amegakure, was danger. Being another kid in Mera's ward—hungry and crying, full and sleeping—was survival.
Nevertheless, he observed her.
Mera-san hummed softly sometimes, never an entire song. Just fragments. Low, barely audible hums that dissolved into the beat of the rain. She mumbled names sometimes too. Names of children who were no longer there.
Never his though. He wondered if anyone knew his name
"Shura would have cried louder than this one," she said at one point, scrubbing Kagerō's hair dry with a frayed towel. "Quiet ones don't survive long."
That said something.
She remembered the ones who didn't survive.
That evening, he watched her carefully, eyes half-closed in pretended sleep, limbs relaxed. She sat by the broken window, drinking watery tea, shoulders hunched inwards like a person struggling to keep in too much sorrow. Her uniform was mended in spots, but not out of affection. Her boots were worn down to the heel. A kunai pouch hung at her hip. Always. Even in the nursery.
He remembered watching her sketch it with breathtaking haste.
A shinobi kid, older, perhaps five, had attempted to pilfer rations from her cart. She didn't reprimand him. She simply shifted. Quick, hard, frightening. The boy was paralyzed, his small hands still buried in the rice crackers.
"Stealing's a quick path to the grave," she had stated bluntly. "Quicker than the war, even."
Then she gave him one.
Just one.
Mera was complex like that.
And Kagerō, despite all his present softness and smallness, made a mental note: People like her live. Not because they are loved. Not because they are kind. But because they are sharp and needed. The world had respect for that.
__________________________________
His days had a rhythm that blurred the boundaries between sameness and survival.
Mornings: feedings, diaper changes, and half-hearted lullabies.
Afternoons: sleep, punctuated by meditation.
Evenings: chakra tracing and watching.
Occasionally he'd simulate babbling or grasping toys to maintain suspicion at bay, but actually, he was always tuning in inward, either on the chakra flow in his body or on adults passing along the halls.
Guards changed shifts at the same hour every day. The youngest of them, Kura, kept forgetting to re-strap his armor. Another, older one, Rekan, limped, always turning on his right side. Kagerō recalled each of them.
He learned the scent of rust and gunpowder.
He memorized the flavor of iron in his milk.
He learned to sleep with one eye just barely open.
Not because anyone would hurt him now.
But because one day, they could.
And he didn't want to die crying in a crib.
__________________________________
His second discovery was slower in coming.
Unlike the first, which had burst upon him with sensation and warmth, this one insinuated itself.
Quietly & Systematically.
A whisper, not a revelation.
Kagerō set out mapping the flow of chakra in his body, not only sensing its presence but tracing it. In which direction it flowed. What rhythm does its pulse beat? How it felt against his skin. It wasn't enough to sense chakra now; he must know it, chart it with the desperate ravenousness of a starving man for power, for purpose.
His mind, adult in attention, infant in constraint, worked as best it could. Silent hours were spent motionless, eyes half-closed in false sleep as his attention shifted entirely inward.
The tenketsu were numerous, far too many for his little body to comprehend them all at one time. So he worked in segments, arms one week, back the following. Chest, neck, head. Down to the tips of his toes. Each node an entrance. Each line between them a route. Each misstep a collision with exhaustion or lightheadedness.
Chakra ran like water, but water as well could be molded. It could be dammed. It could be redirected. It could be frozen or boiled or poisoned.
His chakra control was not close to complete. Sometimes it flared and went out at mid-palm and left him with tingling, stiffened fingers. Occasionally, he over-channeled and passed out in the middle of his breath, waking up battered and drowsy. But slowly, steadily, it came easier. Not easily...but sort of like a second skin.
The meditation aided.
And so did the questions.
Why did chakra seem to come together after traveling?
Why did it become denser, heavier, and more manageable the longer it remained in him?
Why did mental exhaustion numb his flow so badly?
And, perhaps most disturbing of all, why did it seem to be alive?
He didn't know.
Only guesses. Hypotheses.
But while others would have left it at confusion, Kagerō recorded patterns. And patterns, he knew, were only the surface of understanding. One day, they might turn into principles. And principles could turn into techniques. Maybe even jutsus of his own.
__________________________________
Most fascinating to him, as of late, was the peculiar duality of chakra's elements. The spiritual and the physical.
The spiritual was simpler, in a way. It obeyed will. It originated in the mind. But it was transitory, capricious. It went wild when his mind was keen and concentrated but dulled rapidly when fatigue took hold. The mental exhaustion struck like a hammer: a haze behind the eyes, a throbbing pain at the nape of the neck, and the crawling feeling that his thoughts were oozing away from him like sand leaking through his fingers.
The physical aspect was recalcitrant. More difficult to call up, more difficult to sustain. It was drawn from the body, and the body did not surrender it without a struggle. With each effort to draw upon it, he was left more hungry. He could sense the loss of it as if meat was being carved from bone. And when that occurred, the body struck back.
His limbs would hurt. His stomach would twist. He'd collapse into sudden, suffocating sleep. Once, he even passed out, eyes wide but empty, for a minute. The matron had believed him dead and slapped him hard on the back to wake him up.
He didn't make that error twice.
And the seal.
The accursed mark Hanzo had burned into his neck.
It responded when he had used too much chakra. Initially, it was frightening. A slow, smoldering ooze of pain, like venom seeping from an invisible injury. The feeling wasn't bodily, it was one of energy. Like something within him was disintegrating, warning him.
He believed it could kill him.
But it didn't.
Three months went by, and he saw something. With every cycle of exhaustion, his chakra would persist a little bit longer. His body was developing. Physical strength, though meager, was being pulled with greater efficiency. The venom spread less. Still hurtful. Still deadly. But controllable.
It was as if his resistance was increasing.
He started recording, mentally, the mechanics of energy consumption. Chakra was the coming together of body and mind, but sometimes they did not wish to combine. One grew with movement and food. The other with meditation and thoughts. Balancing them was difficult. More or less impossible.
And worse yet: his food was limited.
An orphan didn't receive second helpings.
Which meant he couldn't muscle his way to bigger reserves, not physically. Not until he achieved independence. Until then, he'd have to depend on honing his spiritual advantage. Developing that aspect of the equation.
But even there, constraints awaited.
His mental maturity was borrowed from another life. A bonus he'd stolen from death. But there was no reason to believe it was infinite. He hadn't been a genius in his last life. Eventually, the gap would close. He'd reach the mental maturity of his current body and the advantage would vanish.
He needed more data.
---
Mera, in her non-stop muttering, provided some. She spoke more than she knew. Perhaps because she assumed babies didn't know. Or perhaps, just perhaps, she found a kind of therapy in speaking to someone who couldn't reply.
Kagerō didn't mind.
He listened.
She talked of "dull-eyed ones" who cried too early. Of babies who "fell silent before their time." And once, when she changed his diaper with her characteristic gruffness, she said something that hit him like a lightning bolt:
"The quiet ones always die first."
Kagerō couldn't get it out of his head.
Kruna, another of the boys, was one step away from being comatose every day. He didn't cry, even when his diapers were well past due for being changed. He didn't move much at all. And when he did, it was slow and reluctant. Kagerō had seen that stench before Mera had. He had seen Kruna writhing in agony and say nothing.
He wasn't alone.
A number of the quiet children, those who cried less, fidgeted less, lived less, were pale and thin and slow to grow. Their chakra, when he reached out just far enough to feel it, was weak. Barely there. As though the spark within them had already burned low.
But the loud ones, the screamers, the tantrum-throwers, the emotionally unstable, had intense spiritual power. They illuminated the nursery like firecrackers. But they burned out fast. Their bodies could not handle the burden of their feelings. Their chakra sputtered and disappeared, leaving them flushed and out cold.
Neither group prospered.
From this, Kagerō developed a theory: reserve growth needed balance. Body and mind needed to meet. Not enough physical energy and the spirit flailed. Too much mental energy with no fuel burned itself out. Both needed time, training and resources.
He had none of those.
So he'd improvise.
Now, if only he had more test subjects.