Sleep came in fragments.
He dreamed of operating rooms and sterile fields, of scalpels that turned to kunai in his hands, of patients whose faces melted like candle wax when he tried to save them. He dreamed of a woman's voice calling a name he couldn't quite remember, and of a nephew who wouldn't stop talking about ninja villages while he pretended to listen.
He woke to grey dawn light filtering through canvas and the sound of someone dying three cots over.
Not dying, he corrected himself as he came fully alert. Being treated. The sounds were similar—the wet gasps, the bitten-off screams—but the medic's steady murmur suggested intervention rather than end-of-life.
He lay still for a moment, taking inventory.
Ribs: still fractured, but the sharp grinding had dulled to a persistent ache. Someone had wrapped them while he slept—tight bandages that restricted his breathing but stabilized the bones. Professional work.
Shoulder: stiff, swollen, functional. He'd set it well enough. The joint would be weak for weeks, but it would hold.
Head: the concussion fog had lifted. His thoughts came clearer now, sharper, though whether that was healing or simply adaptation he couldn't say.
Body: still wrong. Still too small, too young, too other. But the visceral horror of yesterday had faded to a dull background unease. He could work with unease.
He sat up slowly, testing his limits. The tent had emptied somewhat during the night—casualties evacuated or expired, he supposed—and weak sunlight painted stripes across the remaining cots. Most of the wounded were sleeping. A few sat propped against their pillows, staring at nothing with the thousand-yard gaze of combat survivors.
He recognized that look. Had seen it on soldiers in the VA hospital where he'd done his residency rotation, a lifetime and a world ago.
Focus.
Right. He had objectives.
First: assess his current situation. Resources, capabilities, immediate threats.
Second: understand this body's baseline. What could it do? What did it know?
Third: plan the next steps toward Konoha proper.
He swung his legs over the edge of the cot and stood. The motion drew no attention—the medics were occupied, and the other wounded had their own problems. He found his equipment stacked neatly beside the bed: the pouches, the kunai, the short sword, the scavenged supplies. Someone had cleaned the worst of the blood from his clothes.
Small mercies.
He dressed methodically, checking each item as he secured it. The kunai fit his grip naturally—muscle memory again, that uncanny sense of a body knowing things the mind had never learned. The short sword was heavier than it looked, but the weight felt right across his back. Balanced. Familiar.
You were a soldier, he thought at the absent Tatsuya. You trained for this.
He wondered, not for the first time, what had happened to the original owner of this body. Had there been a soul here before him? A consciousness that was now gone, overwritten, erased? Or had the body been empty—dying, already dead—and he'd simply filled the vacancy?
Does it matter?
He was getting tired of that question. But no, it didn't. Not practically. The original Tatsuya Meguri, whoever he'd been, was gone. There was only the surgeon now, wearing a dead boy's face and trying to figure out how to survive in his world.
Philosophical implications could wait.
He slipped out of the medical tent and into the camp proper.
The forward camp was larger than he'd realized in yesterday's exhausted haze. Maybe two hundred personnel, split between combat shinobi and support staff. The fortifications were earthwork and timber, hastily constructed but solid—defensive positions for a unit expecting attack.
He catalogued details as he walked. Guard rotations at the perimeter—four-hour shifts, from the conversation he overheard. Supply depot to the north, marked by stacked crates and the smell of preserved food. Command tent at the center, distinguished by the extra guards and the steady stream of messengers coming and going.
And everywhere, the leaf symbol. Stitched into uniforms, carved into wooden posts, painted on banners that hung limp in the windless air.
Konoha. The Village Hidden in the Leaves. His nephew had called it one of the "big five," whatever that meant. The protagonist's home, he thought—though the details were fuzzy, half-remembered fragments from conversations he'd only half-attended.
Should have paid more attention.
Too late for that now.
He found a quiet spot near the edge of camp—a fallen log overlooking a ravine, far enough from the bustle that he could think without interruption. He sat, ignoring the protest from his ribs, and began his real inventory.
Not equipment. Capabilities.
He held up his hands and looked at them. Really looked, the way he'd learned to look at X-rays and MRI scans, searching for what wasn't obvious.
They were calloused in specific patterns. The index and middle fingers of his right hand, the web between thumb and forefinger, the heel of his palm—all thickened from repeated friction. Weapon training. Hours upon hours of it, judging by the development.
He made a fist. Released it. Made it again, faster. The motion was smooth, automatic, utterly unlike the clumsy grip of an untrained child.
Okay. So the body had skills. Combat skills, at minimum. That was something.
What else?
He thought about the word "chakra" and felt something shift inside him.
It was subtle—a warmth in his chest, a sense of potential energy coiled and waiting. He focused on it, trying to understand what he was perceiving, and the warmth intensified. Not painful, but present. Undeniable.
Chakra, he thought. This is chakra.
In the manga, it had been depicted as a kind of spiritual energy—life force mixed with physical vitality, channeled through a network that paralleled the circulatory system. He'd dismissed it as fantasy, the usual pseudoscience that populated fiction. But feeling it now, feeling this thing inside him that responded to his attention like a muscle he'd never known he had...
Fantasy. Right.
He tried to do something with it. Pictured the energy flowing to his hand, concentrated there, manifesting as—as what? Light? Force? He didn't know the mechanics, didn't know the first thing about how any of this was supposed to work.
His hand tingled. Warmth gathered in his palm. And then—
Nothing.
The sensation faded. The chakra—if that's what it was—dispersed back into wherever it had come from, leaving him with nothing but a vague sense of potential unrealized.
Okay, he thought. So there's something there. But I don't know how to use it.
That tracked with his assumed identity. A genin—the lowest rank, fresh from training—wouldn't have mastered anything significant. The body had foundations, but building on them would require knowledge he didn't possess.
He'd need to learn. Carefully, without revealing how much he'd apparently forgotten.
"You're supposed to be resting."
He didn't startle. The surgeon in him had learned not to startle—sudden movements in an OR could be catastrophic—and that training held even now, in this alien context. He turned his head slowly and found the young medic from yesterday standing a few feet away, arms crossed, expression caught between annoyance and concern.
"I was restless," he said. "The tent was crowded."
"The tent is a medical facility. You're a patient. Patients stay in medical facilities until they're discharged." She moved closer, studying him with clinical attention. "Let me see your ribs."
"They're fine."
"I'll be the judge of that."
He considered arguing. Decided it wasn't worth the energy. He lifted his shirt.
The medic's hands were cool and professional as she probed the bandages, checking the wrap's integrity, pressing gently to assess swelling. Her chakra—he could feel it now, a faint warmth that seeped from her fingertips—did something to the tissue beneath. Diagnostic, maybe. Scanning for damage he couldn't see.
"Two fractures," she said finally. "Hairline. You're lucky—another inch and you'd have a punctured lung." She stepped back, apparently satisfied. "You set your own shoulder?"
"Yes."
"Clean reduction. You've had training."
"Some." The lie came easily. "Field medicine basics."
She nodded, accepting this. In a world where child soldiers were apparently commonplace, a twelve-year-old with medical knowledge probably wasn't unusual.
"Keep the wrap tight. No strenuous activity for at least a week. If you feel sharp pain or difficulty breathing, find me immediately." A pause. "What's your name?"
"Tatsuya. Tatsuya Meguri."
"I'm Aiko." She didn't offer a family name. Perhaps she didn't have one. "You're the one who brought in the civilian girl?"
"Yes. Is she—"
"She's fine. Physically, anyway. Emotionally..." Aiko shrugged, a gesture that conveyed exhausted helplessness. "She'll be evacuated with the next convoy. There's an orphanage in Konoha that takes war refugees."
Orphanage. Of course. Because in this world, there were enough orphaned children to require dedicated infrastructure for processing them.
He filed that away and asked: "When's the next convoy?"
"Tomorrow morning, if the roads stay clear. You're on the manifest—all walking wounded are being moved back. The camp's relocating east, and they don't want to leave casualties behind enemy lines."
Tomorrow. One more day here, then transport to Konoha proper. He could work with that.
"Thank you," he said. "For the treatment."
Aiko's expression flickered—surprise, maybe, at gratitude from a patient. "Just doing my job." She turned to leave, then paused. "Get some rest, Tatsuya. You look like you need it."
She was gone before he could respond.
He spent the rest of the morning observing.
The forward camp was a wealth of information for someone who knew how to watch. He found an unobtrusive position near the supply depot—close enough to see the comings and goings, far enough to avoid suspicion—and let his surgeon's attention catalog everything.
The shinobi moved differently than normal people. Not just faster or more gracefully, though they were both; there was an awareness to them, a constant peripheral attention that never quite relaxed. They tracked movement instinctively, repositioned to maintain sightlines, kept their hands free and their backs to walls.
Combat readiness. Ingrained to the point of unconsciousness.
He watched a pair of chuunin spar in an open area near the perimeter. No weapons—just taijutsu, hand-to-hand, though "hand-to-hand" didn't quite capture what they were doing. They moved at speeds that shouldn't have been possible, strikes blurring, bodies twisting through angles that defied normal biomechanics.
Chakra enhancement, he realized. They were using that internal energy to augment their physical capabilities. Faster reflexes, stronger muscles, maybe even reinforced bones. The applications were—
Staggering. The applications were staggering.
If chakra could do that—if it could be channeled to enhance the body beyond natural limits—then the implications for medicine alone were revolutionary. Healing, surgery, rehabilitation... all of it could be transformed by energy that could be directed with conscious intent.
He thought about the melted face on the battlefield. The precision wound. The paper tags covered in unreadable symbols.
And the destructive applications, of course. Couldn't forget those.
Around midday, he found Yuki.
She was sitting outside one of the administrative tents, knees pulled to her chest, watching the camp with hollow eyes. Someone had given her clean clothes—simple civilian wear, brown and undyed—and a ration bar that sat untouched in her lap.
He approached slowly, giving her time to notice him. She looked up when he sat down beside her but didn't speak.
"How are you feeling?"
Stupid question. She was eight years old and had watched her family die. How was she supposed to be feeling?
But Yuki considered it seriously, her brow furrowing in thought. "Empty," she said finally. "Like there's supposed to be something there, but it's just... gone."
Dissociation. Emotional numbing. Classic trauma response, and probably protective—her mind shutting down what it couldn't process.
"That's normal," he said. "After what you've been through. It won't feel like this forever."
"How do you know?"
Because I've seen it before. Because I've talked to survivors in hospital beds, held hands with people who lost everything and somehow kept going. He couldn't say any of that. Instead, he said: "Because nothing lasts forever. Not even the bad things."
Yuki was quiet for a long moment. Then: "The lady said I'm going to an orphanage. In Konoha."
"Yes."
"Are you going to Konoha too?"
"Yes."
"Will you..." She hesitated, looking down at her hands. "Will you visit? Sometimes?"
The request hit him harder than it should have. He barely knew this girl. They'd spent two days together—two terrifying, exhausting days—and that was all. She wasn't his responsibility. He had enough problems without adding an orphaned child to the list.
"Yes," he heard himself say. "When I can."
She nodded, something unknotting in her shoulders. "Okay."
He stayed with her until a camp administrator came to collect her for processing. She went without protest, just a small wave over her shoulder as she disappeared into the tent.
He watched her go and wondered what the hell he was doing, making promises he might not be able to keep.
Survive first.
Right. But survival wasn't just about staying alive. It was about staying human. Keeping the parts of yourself that mattered, even when everything else was stripped away.
He'd learned that in the surgical ward. Watching patients who gave up versus patients who fought. The difference wasn't physical—it was having something to hold onto.
Maybe Yuki could be that. A reminder that he wasn't just a consciousness dropped into a foreign body, struggling to navigate an impossible situation. He was a person. He had connections. He had responsibilities.
He had reasons to keep going.
That afternoon, he found a secluded training area—a small clearing behind the supply depot, screened by trees and apparently unused—and began testing his body's limits.
It started with basic movements. Stretches. Stances. The kind of foundational work that any martial artist would recognize. His muscles knew what to do; the forms emerged from somewhere beneath conscious thought, flowing one into the next with practiced ease.
The Academy, he thought. Wherever Konoha trained its child soldiers, they'd drilled these movements into him until they became automatic. Good. Automatic was useful. Automatic didn't require explanation.
He moved through the forms slowly at first, then faster as his confidence grew. His ribs protested, but the pain was manageable—the sharp edge of fractures masked by the persistent ache of exertion. He could work through ache. He'd done it before, in forty-hour shifts and double-booked surgeries and all the other small hells of medical training.
The taijutsu was rudimentary. He recognized that even without formal comparison—the movements were simple, efficient, designed for practicality over elegance. A genin's foundation. Something to build on, not a finished product.
But within those limitations, the body performed well. Fast, for its size. Coordinated. Stronger than it looked, though whether that was natural or chakra-enhanced he couldn't tell.
He tried weapons next.
The kunai felt like an extension of his hand. He threw it at a tree trunk twenty feet away—and missed badly, the blade spinning wide and burying itself in the dirt.
Okay. So muscle memory had limits. Knowing how to hold a weapon wasn't the same as knowing how to use it effectively.
He retrieved the kunai and tried again. Missed again, though closer this time.
Third throw: hit the trunk, but with the handle instead of the blade.
Fourth throw: solid impact, edge-first, maybe six inches from where he'd aimed.
Progress. Slow, frustrating progress, but progress nonetheless.
He practiced until his arm burned and his ribs demanded rest. Then he sat in the grass, breathing carefully, and thought about what he'd learned.
The body had foundations. Real ones, drilled deep by training he didn't remember. But foundations weren't mastery. He was functional—capable of basic combat, capable of survival—but nothing more. In a world where people could spit fire and melt faces with a gesture, "functional" wasn't going to cut it.
He needed to train. Seriously, systematically, with the same obsessive focus he'd brought to surgery. Learn the rules. Master the techniques. Build on what this body already knew until he was something more than a walking target.
But first, he needed to understand what he was working with. The chakra he'd felt that morning—how did it function? How was it controlled? What were its limits, its applications, its costs?
He closed his eyes and reached for that inner warmth again.
It responded more easily this time. A gentle pressure in his core, like a held breath waiting to be released. He let it build, let it gather, then tried to push it toward his hand—
The world shifted.
Not physically—he didn't move, nothing around him changed—but his perception altered in a way he couldn't quite describe. Suddenly he was aware of... more. The texture of the air. The pulse of the earth beneath him. The distant hum of other presences—the shinobi in camp, each one a small sun of contained energy.
Chakra sense, he realized. He was sensing chakra. Not seeing it, exactly, but perceiving it through some additional faculty he hadn't known he possessed.
The camp blazed with it. Hundreds of individual signatures, ranging from the guttering candles of the wounded to the roaring bonfires of what must have been elite shinobi. He could feel them all, a tapestry of energy woven through the world around him.
And beneath it all, a current. A vast, slow-moving river of something that felt less like chakra and more like... life itself. The forest. The earth. The world, breathing.
Then the perception snapped shut, and he was just himself again—exhausted, gasping, his head pounding like he'd been hit with a hammer.
Too much, he thought distantly. Pushed too hard.
He'd overtaxed something. The chakra equivalent of a muscle cramp, maybe—a system not designed for the load he'd put on it. He'd need to be more careful. Build up slowly. Learn his limits before he exceeded them.
But the potential...
He sat in the grass as his headache slowly faded, and for the first time since waking on the battlefield, he felt something that wasn't fear or confusion or desperate survival instinct.
He felt hope.
This world had rules he didn't understand yet. But rules could be learned. Systems could be mastered. Whatever chakra was, however it worked, he could figure it out. Apply the same methodology that had carried him through medical school and residency and a decade of surgical practice.
Observe. Analyze. Practice. Refine. Repeat.
He'd done it before, with nothing but determination and a willingness to work harder than anyone else. He could do it again.
Survive first, the voice in his head reminded him.
Yes. But surviving wasn't enough anymore. He needed to grow. To become something more than a confused transplant stumbling through an alien world.
Konoha was waiting. And when he got there, he'd have work to do.
He made his way back to the medical tent as evening fell, his body aching but his mind clearer than it had been since arrival. The medic—Aiko—intercepted him at the entrance, her expression caught between professional concern and personal exasperation.
"You were supposed to be resting."
"I was. Then I needed to move around." Not quite a lie. "I'm careful with the ribs."
She studied him for a long moment, clearly unconvinced, then sighed and stepped aside. "Convoy leaves at dawn. Get some actual sleep. You look like death."
"Noted."
He found his cot and lay down, staring at the canvas ceiling as the tent slowly darkened around him.
Tomorrow: Konoha. A village he'd only half-heard about, in a world that shouldn't exist, wearing a body that wasn't his.
No pressure.
He closed his eyes and let exhaustion pull him under.