The script was simple, immaculate, and utterly compelling. The Transmigrator's Covenant: A soul from an another world finds passage into the body of a fictional character. The knowledge of the future—a sacred gift—fuses with the character's inherent power. They become the architect of destiny, a living, breathing cheat code. They are elevated to the pedestal, their every strategic move lauded. They become the Hokage, the benevolent conqueror, the Savior hailed by every tear-streaked eye in the world. Everything, in that glorious, self-congratulatory narrative, proceeds perfectly.
Then why? Why, in the name of every cosmic law and literary trope, did my own transmigration begin with the scent of burning flesh and the chill of utter failure? I was the one with the answers, the ultimate advantage. Yet, I had already derailed the story into a thousand-fold tragedy.
It has been barely eighteen months. A paltry year and a half of inhabiting this cursed body. And yet, the cost of my integration is measured in the thousands. Thousands of human lives, extinguished by the unchecked power of this borrowed body and the chaotic trauma festering in my mind. They were not nameless bandits. They were the proud, disciplined shinobi of Sunagakure and the stoic, iron-willed warriors of Iwagakure.
And among the rubble, a single, devastating truth: I had killed the Tsuchikage.
The sheer scale of the atrocity was now a physical affliction. I hadn't just murdered soldiers; I had decapitated a Great Nation. I had invited war, chaos, and global retribution. I was not a hero, but a geopolitical disaster, a walking, breathing casus belli.
A scorching, metallic tide of bile surged into my throat. I swallowed it, choking on the rising self-hatred, forcing my legs to continue the agonizing, endless march. I had run for a full day, the need for motion a desperate, primitive urge to outrun the ghost of my deeds. Orochimaru's foul lair—the next desperate focus—should be close. I was running toward one monster to distract myself from the greater monster I had become.
The blessed sound of rushing water, a cruel melody of purity, had drawn me from the oppressive woods. I fell onto the bank, plunging my face and hands into the frigid stream. The water was a shock, a sudden, needed break from the fever of my mind.
As the frantic heat receded, the devastating truth of the slaughter rushed in like an icy torrent, bringing with it the crystalline clarity of my shame.
The Guilt.
I killed them. Reduced seasoned shinobi, men fighting for a righteous cause—the retrieval of kidnapped children and the neutralization of a global threat—to nothing but paste. I killed the Tsuchikage, the pillar of a people, a leader whose life held the balance of power. And the genesis of this monstrosity? It was a sick joke. It was the physical revulsion of having to travel through the damned snake's smelly mouth. No, that was superficial. It was the legacy of the Uchiha massacre. The years of emotional starvation under a father who offered only cold scrutiny. Itachi's broken, bloody promise. The soul-crushing realization that every defining moment of this body's life had been a cruel manipulation—nothing but a pawn in a game I thought I was now controlling.
I had spent my entire life desperately suppressing my emotions. I crushed the genuine roar of my heart, desperate to maintain that flawless, perfect Uchiha image—the prodigy, the avenger, the controlled machine. The pressure had built up, a geological force contained within a cracking shell. And those shinobi, seeking only to stop a child-kidnapper, had been the final, fatal weight that tipped the scale over the edge.
I lost control of my emotions. And I killed thousands because of it, crippling two nations seeking only justice.
They were heroes in the making, seeking to punish Orochimaru, a monster who kidnapped and experimented on children. They were striving for simple justice. And I, the self-proclaimed future Savior, had executed them for their virtue. I had protected a monster and become a greater one in the process.
I stared into the dark sheen of the water. The face looking back was the beautiful, cursed visage of Sasuke Uchiha. But the eyes—they were haunted, reflecting the terror of an uncontrollable power and a shattered soul.
"A sinner," I rasped to the reflection. "An utterly inhumane being. A Kage-killer."
A creature who killed thousands. I tried to anchor myself in the past, in the life I remembered.
If my parents from my previous, safe world saw this, what would they call their son? A killer? A psychopath? The titles didn't matter as much as the look in their eyes. What would my little sister, my sweet, naive, lovely sister, say if she saw the blood on my hands, the vacant horror in my gaze? The thought of her innocent disappointment was a pain sharper than any lightning jutsu. It was the absolute, final loss of myself.
And my parents here? My Uchiha mother, Mikoto. Her gentle nature would shatter at this sight. But my Uchiha father, Fugaku? A bitter, sickening thought surfaced: maybe he would finally be proud. Proud that his son had committed an act of devastation comparable in scale to the legendary Fourth Hokage, or even the First. Brutality earned status in this ninja world. He was the same man who traumatized Itachi with the horrors of war at age four, setting the stage for the clan's end.
And Itachi. He killed his entire clan as a thirteen-year-old child, out of an impossible, heart-wrenching duty. He had no choice; his capacity to find an alternative was strangled by the Elders.
But I? I had a choice. I had the knowledge of the future! I could have used Reverse Summoning. I could have outpaced them. I could have paralyzed them without killing. But no. I killed them because of my sheer frustration.
The thought was a physical blow: Original Sasuke was a better human than me.
The irony was a venomous bite. That version of Sasuke, the one fueled by blind, raw vengeance, never killed a soul while under Orochimaru's wing. He only struck down those he deemed truly heinous, and even then, he showed an unsettling measure of control. When confronted by the Samurai blocking his path to the Elder Danzo, a man who stole Uchiha eyes, he asked them to step aside, recognizing their lack of malice. He gave them a choice. Later, he abandoned his own vengeance against Konoha because he deemed it a worthy legacy of Itachi's sacrifice, a decision based on emotional logic I could barely grasp.
If that Sasuke, the one fueled by vengeance, saw the massacre I just committed—thousands dead, a Kage slain, two nations destabilized—for no reason but my temper—would he kill me for being such a monstrous, inhumane failure? The answer, a chilling, undeniable yes, resonated in the stillness of the night.
A humorless, agonizing sound tore from my chest. Hahahaha! And here I was, talking about being the Savior of the World. Was I truly destined for anything other than isolation and destruction?
Could I ever look at my own face without seeing it with blinding disgust? The face of a man who massacred thousands, who murdered a Kage? I reached up, rubbing the cold water across my eyes, wishing I could physically scrub the image of the dead from my mind.
But the question of redemption no longer mattered. I couldn't be redeemed. The time for absolution was gone, swept away in a torrent of blood. And the terrifying truth was, perhaps I didn't want to be. Maybe this horrific, lonely path was the destiny I was never meant to escape, even with the cheat code of future knowledge. The soul-fusion wasn't a clean slate; it was a blend of two deeply scarred entities, amplifying the darkness.
I was meant to walk alone.
Yet, amidst the crushing despair, a flicker of light: the memory of a certain blonde-haired knucklehead. Naruto. In the original, Naruto was the absolute light, the spiritual force that dragged Sasuke back from the abyss, the one who held the line of humanity.
But here, there was no Naruto. There was only a girl: Nanami. An anomaly, a variable. Could she, a deviation from the script, possibly hold the key to saving this corrupted soul? The hope was too frail, too terrifying to entertain. To seek her light would be to endanger it.
I shoved the thought away, focusing instead on the raw, undeniable facts of this world: injustice. The Uchiha massacre, those smiling children in Orochimaru's cells. The world was rotten to the core.
I rose from the riverbank, leaving behind the last vestiges of clean water and hope. My path was set. I will change this world. There will be no more injustice, no more pawns, no more massacres engineered by the powerful.
But I won't do it as the Savior. I will do it as the Sinner, the controlled instrument of destruction. I will accept my eternal fate—sacrificing myself to the shadows, never seeking light, fighting the darkness from within the darkness, until the world is safe.
I turned my back to the river and faced the hidden entrance to the serpentine lair. The cold, damp stone was covered in old, complex seals, but my eyes—the Sharingan—read them like a child's book. As I performed the release signs, the great rock groaned, opening into a black maw.
Before descending, I looked one last time at the sliver of the night sky, etching the memory of that unattainable starlight into my mind. I would carry that image into the abyss, not as a goal, but as a painful contrast—the eternal reminder of what I forfeited the moment my frustration turned into mass murder.
The very essence of my existence had become a paradox: I, the murderer of thousands, the slayer of a Kage, was now the only one capable of wielding the necessary cruelty to fix a world built on cruelty. My self-imposed penance was not just walking in the dark, but fighting for the light I could never touch.
I took the first deliberate step onto the cold, dusty stone of the staircase. The air immediately grew colder, heavier, smelling of chemical residue and human fear. Every shadow seemed to stretch and welcome me home.
This is it. The point of no return.
I was no longer seeking redemption. I was seeking expiation—a cleansing through action, a constant, tireless fight against the darkness that justified my existence, even if I could never justify my deeds.
I am the Sinner. And the Sinner will save this world, not by bringing the light, but by ensuring the darkness never consumes what little light remains. Even if it means living in the darkness for the rest of my life, never seeing light again in my entire life or even eternity.
I descended deeper into the earth, toward Orochimaru's base. The future of the world was no longer a story I was trying to correct. It was a battlefield where I, the self-appointed executioner, would fight until I broke or until the world was finally safe from the likes of me. My journey had begun not with a glorious awakening, but with a horrifying, thousand-fold slaughter. It would end when the last thread of injustice was cut, even if that thread was the one sustaining my own miserable life.
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Author Note :
I actually wanted to write it with the previous chapter, but the chapter was already too long, so I made a new chapter.
And about the chapter, I always saw Sasuke as person who had stronger sense of justice, as in Boruto he is always about redemption journey, so I believed if he in his right mind killed innocents, then he is bound to have a breakdown. Which is where I would develop his character to my liking. Also don't leave the fanfic just because of this chapter, as this is just his one of the first character development. You will see more later. I don't wanna spoilt it now.
This chapter also gave his moral belief a more clear view, as I think in previous chapters I failed to do so.