Night in Konoha is supposed to be quiet. It wasn't.
The orphanage door crashed open under the weight of fear dressed as courage. A dozen villagers—faces tight with drink and grief and a kind of righteousness that grows in shadows—poured inside. Boots scraped across old wood. A matron in a night robe tried to stand in the hallway and said something about children, about sleeping, about mercy. She was pushed aside like a curtain.
In a cot near the far window, a two-year-old boy with a sunburst of hair slept with his fist curled under his cheek. He had no idea the world had already named him.
"There," someone hissed. "The demon."
Another voice trembled, not from pity but from anticipation. "Get it over with."
Hands grabbed the blanket. The boy woke, blinked once, and reached for the blanket the way infants do, as if life is a thing you can cling to. The men did not look at him. They looked through him—at a night thirteen years ago, a nine-tailed silhouette roaring over fire, at wives and sons and fathers who never came home. Their anger needed a face. He had one.
They hauled him from the crib. The matron lunged and took an elbow to the ribs. She went down without a sound. Two women hovered in the doorway, eyes bright and wet, whispering "don't" without moving. No one listened.
The first blow was clumsy—rage is a bad teacher—but it landed. Then the next, and the next. He cried like any child, a high broken noise that should have summoned mercy. It summoned more fists.
Realistic but restrained; that's how truth sometimes looks. There was no artistry to this. Skin bruised. Lips split. The breath went in and wouldn't come out for a second that felt like a year. His tiny fingers kept trying to protect his face and kept failing. Outside, night wind dragged a chime across the eaves and made a single note, lonely and long. Inside, someone said, "Enough," and someone else said, "Not yet."
They didn't see the man in the street pause.
A pale figure with yellow eyes stood beneath a lantern, the light breaking across his face like a mask. He was just passing through—curiosity on legs, wrapped in a robe, soft sandals whispering. He wasn't here for heroics. He was a scientist who had cut the word "ethics" from his dictionary long ago.
Orochimaru watched the mob through the slat of a window. Emotions were nothing to him unless they made people predictable. What interested him was the child who refused to die.
"Ah," he murmured to himself, that soft reptilian amusement curling his lips. "The jinchūriki."
The matron finally found her voice. "Please," she sobbed. "He's just a baby."
That word. Baby. It shook something dull in the air. Guilt is also a bad teacher, but sometimes it speaks.
The villager with the heaviest hands stepped back. "We should go," he muttered. "Before someone—"
"Someone like me?" Orochimaru said pleasantly from the doorway.
The room froze. Even drunks recognize predators higher up the chain.
He smiled; it didn't touch his eyes. "What a lively night. I'll take it from here."
They fled, because of course they did. The matron crawled, whispering apologies to the boy like bandages. Orochimaru crossed to the cot and looked down. Blood at the nostril. A bruise on the cheek blooming like ink in water. A chest that shuddered too quickly.
"So fragile," he said, fascinated. "So stubborn."
He gathered Naruto like a specimen and slipped back into the night.
The laboratory wasn't one of his grand halls underground. It didn't need to be. A traveling setup: iron table, clamps that could be called medical if you lacked imagination, jars of things that had known light in other lives. The air smelled of herbs and metal.
Orochimaru set the boy down, fingers gentle not from kindness but precision. He'd intended to test resistance—what happens to a jinchūriki's body if you add a variable? Add one heart. Add two. Replace. Augment. Listen to cells sing or scream.
He peeled back bandages and made a clean line on a small chest. The boy flinched in sleep. A tiny breath. Then another. Orochimaru's hands were steady. He worked like a calligrapher writing a forbidden character.
What he found wasn't what he expected.
In the preserved cabinet—a relic he had stolen from a ruin and labeled "unknown"—was a thing that wasn't just a heart. It was black, but not painted; black the way a hole in the world is black. Veins like frozen lightning. It pulsed once when he touched it, a soundless thud that rattled the tools.
"Fascinating," Orochimaru whispered, equal parts scientist and serpent. "What are you?"
He didn't know. No one did. He didn't need to. Curiosity is a blade that cuts before you measure.
He placed the black heart beside the boy's own, threading tiny, meticulous connections, chakra strings thin as hair. He expected rejection, fever, an immune storm. He got nothing. The black heart lay there, inert, as if waiting for a permission no one in this room could give.
His mouth tightened. "How boring."
He sealed the incision with a whisper of jutsu, leaving a scar slim as a sigh. Then he did a mean, precise kindness: he eased the pain, sealed the evidence, and carried the child back to the orphanage. The matron looked up from her prayers and nearly fainted when her baby reappeared in the doorway, clean and breathing, as if night had been a bad dream.
Orochimaru indulged himself with a small lie. "A failure," he said to the air as he left. "For now."
The chime on the eaves made that lonely note again.
Years passed. You could measure them by bowls of ramen eaten alone at Ichiraku, by pranks painted like bright masks, by the number of times Naruto laughed too loudly and looked too long at doorways hoping someone would step through for him.
The scar over his heart was invisible to every scan, to every medic who tutted and said he was healthy. His stamina was ridiculous. His chakra was a forest. But none of that is rare enough to be suspicious in a village that breeds miracles.
Sometimes, late at night, Naruto would press a palm to his chest because something felt off, like an extra beat that wasn't a beat. He never mentioned it. He had more immediate problems: the looks, the whispers, the way adults pulled their children away. He learned early that anger is heavy to carry and smiles weigh less. So he smiled. He yelled about becoming Hokage. He chased attention like it was a flag at the festival and he was always half a step behind it.
Iruka saw him, which is to say Iruka refused to look away. There were small mercies: a forehead protector given with a trembling heart; a teacher whose scar itched when he watched Naruto grin; a bowl of ramen that tasted like being included.
The black heart slept.
Even in the Forest of Death, when a different kind of serpent smiled and bit like a storm, the black heart didn't stir. Orochimaru, facing a loud blond boy atop a swaying branch, felt a flicker of something like déjà vu and brushed it aside as annoyance.
"Run," Sakura screamed.
Sasuke froze, pride a nail in his foot, fear a cold glove on his spine.
Orochimaru toyed with them because that is what cats do, and he left a mark because that is what curses do. He slithered away, pleased with his own cleverness and bored by the boy who should have died ten years ago and didn't. He never connected the quiet scar under those bandages to the numbness he sometimes felt in dreams when a black door opened and something old looked back at him.
The black heart slept.
When people say "Valley of the End," they say it like a title, like a legend that already knows how it will end. Two ancient statues watched a river write itself into the earth, and the air smelled of rain and old promises. Sasuke stood on one statue's head, Naruto on the other, and the distance between them wasn't just stone.
Sasuke's eyes were a furnace behind skin. He wore his sadness like armor and his anger like heat haze. "You don't understand," he said, every syllable measured, because if he didn't measure them they might come out as grief.
Naruto yelled back, because that's how he loved: loudly, stupidly, with everything and then some. "I won't let you go to that creep! We're friends!"
The word friend ricocheted around the valley, a bird that didn't know what glass was, hitting invisible walls again and again.
Sasuke's mouth curled. "Friend? Don't insult me with a word you don't understand."
He moved. Naruto moved. That was the whole conversation for a while—fists and feet and chakra like fireworks, the kind you feel in your bones. They were both too young to fight like that and old enough that they had to.
Sasuke's speed was a clean cut. Naruto's persistence was a tide. Rasengan churned like a captured storm in one hand. Chidori screamed like a thousand birds in the other. Their footfalls carved names into stone only the river would read.
Omniscience is a curse in a moment like this; it lets you see the boy and the pain that raised him, the other boy and the pain that dressed him, and the inevitable math of two trajectories that refuse to curve.
Sasuke's hand shot forward, lightning hungry. He aimed not to kill—he told himself that and almost believed it—but to end. End arguments. End lectures. End the face that reflected the boy he used to be.
The world narrowed to a point where blue met flesh.
Naruto saw the strike coming and didn't dodge. Some of that was bravado. Some was trust that had nowhere else to go. Some was a secret he didn't know: a black heart waiting for a password.
Chidori pierced. There was blood, bright and shocking, and a sound like a held breath breaking. Naruto staggered, then fell backward off the statue's brow. The sky flipped. The river opened its arms.
Sasuke's eyes followed him until the spray swallowed the orange and blue. He stood panting, chest heaving like a door in a storm, and told himself this was necessary. He turned away because turning back would have looked too much like regret.
Underwater, the world went quiet. Light folded itself into the river in trembling ribbons. Naruto's body went heavy. He thought of ramen, of Iruka's forehead protector, of a swing on a playground that never stopped moving because he was never allowed to sit on it for long. He thought of a promise to never go back on his word. He thought of a face framed with black hair saying friend like it tasted bad.
His heart misfired.
The black heart opened its eyes.
Not literally; it had no eyes. But there was an awareness in the dark—an ancient, patient readiness—as Naruto's life spilled like ink in water. It did not understand words like "boy" or "village." It understood fuel and silence and orders engraved in its substance like commandments.
Chakra brushed it. It drank.
It began gently, almost polite: a sip from the boy's own well, tasting wind-natured chakra and the stubborn flavor of a child who wouldn't surrender. Then it tasted something deeper, hotter, a sea behind a gate: the Nine-Tails' rage, the tectonic plates of hatred shifting in their sleep.
The black heart did what it was made to do.
It pulled. Threads of blue unwound from Naruto's coils, spiraling toward the dark like river eddies pulled into a cave. The seal that had been fox and father and fate thrummed as if in alarm; then, as Naruto's breath fluttered, the seal's resistance thinned—not because it was weak, but because something older stepped past it like a tide through reeds.
On the riverbank above, the statues watched water churn. The spray rose like a veil. Far away, sensors would later speak in frightened tones about a pulse of negative energy spreading ten kilometers like a storm that wasn't weather.
In the depths, the black heart felt the Nine-Tails. Felt its heat. Felt its ancient anger. It didn't flinch. It did not have room for fear.
It drank deeper.
Kurama's chakra roared in its cage. Then—something strange. The hatred that had fed on hatred for a century felt… lighter. As Naruto's own pain siphoned away, strands of malice began to lift, like smoke finally finding a chimney. The cage bars glowed, not with prison light but with absence—hatred leaving a place it had long called home.
Above hatred, something else stirred. A presence. A god with a sword and a rope and a mask, pausing on a shoreline no mortal feet had ever touched. The Shinigami tilted his head, watching a tiny human soul tumble in the water and a dark heart eat light like it was starving.
"Hm," said the god, in a voice that didn't need sound. "What an odd mistake."
He reached into his stomach and pulled out a different light—bright, familiar, threaded with love and red hair and the echo of a Fourth Hokage's laugh. He held Fate in one palm and Curiosity in the other and chose to intervene.
But that is the next chapter's story.
For now: the river tugged at Naruto's jacket and hair. Bubbles climbed past his cheeks like escaping thoughts. The world around him dimmed to a deep, cathedral blue. At the center of his chest, the black heart pulsed once—heavy, hungry, decisive.
It found an energy source.
It started to activate.