In the darkness, All For One’s consciousness drifted back through the strata of time.
It was like loading an old, dusty film into a projector. Fragmented memories slowly came together, vividly reviving the air, the scent of that day eleven years ago, and the insolent voice of that child.
Eleven years ago, on that day.
It wasn’t merely the day when a remarkably talented brat walked in on his own two feet. It was the day that first awakened a sense of kinship in All For One—the absolute ruler who could grasp the entire world in the palm of his hand and sway it at will.
When he first took that brat under his wing, the boy struck him like a razor-sharp blade. He wasn’t a rough gemstone waiting to be refined; he was a fragment of a cursed sword, honed so perfectly from birth that it could slice through anything.
A precocious maturity far beyond his years, eyes as cold as if his emotions had been excised, and a weariness that suggested he already knew every secret the world had to offer.
Emotions? To him, they were nothing more than needless static—a mechanical mindset focused solely on efficiency and results.
The child regarded living beings as nothing more than collections of organic matter, and Quirk factors as simple streams of data.
The arrogance with which he looked down upon the world mirrored All For One himself.
That was why All For One kept him close. He cherished the boy’s inherent brilliance, his demonic talent that needed no further instruction.
However.
“Since there’s no failure, it’s not very fun, old man.”
Over time, the child began to change imperceptibly.
With each successful experiment and every theory he flawlessly proved, the boy started to break down—breaking, by All For One’s standards, even as he was becoming more human in the eyes of the world.
Before long, he began lounging in a corner of the lab, nonchalantly yawning.
“Old man, do we really have to do this today? It’s not as if the world is ending tomorrow.”
His meticulous calculations were gradually simplified by a filter of laziness, and his once sharp irritability gave way to a languid indifference.
“Life really requires just the right mix of thrills and failures, but I’m just far too perfect,” he observed.
He seemed to tire of his own perfection. When success was inevitable, the very effort to achieve it turned into dull, monotonous labor.
And somewhere amid that ennui, the child developed a peculiar hobby.
“Oh… that guy’s doing pretty well, huh?”
He began cheering for the experimental subjects—or perhaps for the ordinary people flickering beyond the monitors.
He found a strange fascination not in those with overwhelming power or intellect, but in the ordinary, insignificant ones who struggled desperately.
“Look, old man. That kid over there—he’s giving his all for something doomed to fail. Sentimental and foolish, isn’t he? But… doesn’t it just pull at your heartstrings?”
Resting his chin on his hand, he snickered.
“I like that kind of thing. The stupid, inefficient, emotional kind. Perhaps it’s because I lack them myself? Watching it is pure entertainment—a human drama unfolding before my eyes.”
Gradually, he became a hedonist, paradoxically longing for the very ordinariness in others that he himself did not possess.
Delicious snacks, plush chairs, captivating comic books…
It was as if an old sage, having unraveled all the world’s complexities, shed it all away to return to the innocent play of a child.
“Why do I live like this? Old man, you know that playing is far harder than winning. Conquering the world follows a set formula, but playing—now that’s a game with too many variables.”
That was what the child declared.
And then, six years ago. That day arrived.
The day when that child was both at his most vulnerable and his most ruthless.
The decisive showdown with All Might was imminent.
Deep in a subterranean main laboratory,
the only light came from the low hum of the cooling water pump and the cold blue glow of dozens of monitors.
Under that feeble illumination, a small silhouette was perched atop the central operating table.
The boy, then about ten years old, looked impeccably neat—as if he belonged in a British private school—in a perfectly fitted black suit with shorts, a vest, and even a red bowtie.
He dithered his small, shod feet in the air. Clack, clack. The steady tapping of the table’s legs pierced the silence of the lab like a metronome.
"So, old man. Are you really going?"
He asked, his tone devoid of any worry—as though he were an audience member inquiring about the climax of a riveting play.
"The preparations are complete. There’s no reason to delay any longer," All For One replied.
"Hmm…."
The child popped a candy into his mouth and rolled it around, the clinking sound shattering the silence.
Now considerably grown, he fixed All For One with an insolent, detached gaze, yet his eyes sparkled with a strange amusement.
"Interesting. You really are quite the romantic, old man."
"A romantic… hardly a title that suits the King of Evil," retorted All For One.
"Who said anything about a villain? You’re just a stupid older brother."
The child snickered before leaping from the operating table. The sound of his dress shoes echoed. Clack.
He slowly circled All For One before speaking again.
"The calculations were done long ago. Let me give you the conclusion first."
He raised one finger.
"In this world, there is no longer any living being capable of receiving the Quirk factor of ‘One For All’ and withstanding it."
All For One fell silent. It was a truth he had long suspected.
"All Might is the last. He is a miracle—a vessel possessing the overwhelming durability demanded by the ‘First Gigantomakhia Theory’ and simultaneously embodying the void of being Quirkless, the essence of the ‘Third Theory.’ The sole exception in this world."
The child giggled.
"There is no next generation. Because, old man, you’ve used them all up."
And that was the cold truth.
To empirically validate the child’s theory—and to confirm and extract the will of his younger brother, Yoichi, said to reside within One For All—All For One had gathered Quirkless humans from around the globe, consuming them as experimental subjects.
Countless experiments led by the Doctor and the child had culminated in the theories from First to Third coming to fruition, but at the grave cost of eradicating the “vessels capable of holding One For All” from the face of the earth.
"And even if…"
The child waved his hand dismissively.
"Even if, by some stroke of luck, a Quirkless person survives tucked away in a corner, it wouldn’t matter. Even if All Might forcibly transfers the power to that person, a tenth generation could never be born."
"Is it because of the Singularity?"
When All For One asked, the child simply nodded.
"Ding-dong. The Singularity domain reached by ‘One For All’ has already met its end. That power has exceeded the accumulation phase. The moment it enters the next vessel, that vessel will shatter—whether the brain burns out or the body explodes. In short, the succession of One For All ends physically with All Might’s generation."
The child leapt off the operating table. The sound of his shoe heels tapped merrily. Clack.
He held up one finger as if to punctuate his point.
"There is no next generation. All Might is the last. A physical form capable of harnessing this power no longer exists within the human gene pool."
This was a fact All For One had long come to understand. As the Quirk Singularity accelerated, an accumulation-type Quirk like One For All had become nothing short of a runaway nuclear bomb. If passed on to an ordinary human, it would result in catastrophic failure.
And that meant the experiment with All For One had already ended in failure.
After all, the crux of the Third Project was to pursue Yoichi’s eternal life.
Yet the child continued, amusement evident in his tone.
"So the conclusion is simple."
Leaning close to All For One, the child’s face nearly brushed against his, his breath redolent of candy.
"Just wait twenty more years."
A sweet, almost seductive whisper.
"After twenty years, ‘One For All’ will no longer be able to withstand the brilliance of the Quirk factor that has reached its Singularity—it will self-destruct. Whether the vessel shatters or overflows, it will simply explode. There’ll be no need for you to get up, sweat, and bleed, old man."
He continued,
"If you just sit back and munch on some popcorn, you win—a default victory. How clean is that? Efficient, safe, and sure."
It was the lure of a devilish offer.
A victory scenario so perfectly rational, scientific, and indisputable that it tempted even the most pragmatic mind.
It was the easiest path to break the relentless curse of One For All and to exorcise his brother’s ghost without lifting a finger.
Any ordinary ruler—or any rational villain—would have gladly accepted this plan.
But All For One slowly shook his head.
"No, I must go."
His voice was low, yet as unyielding as a rock.
"I can’t afford to wait twenty years."
"Why? With your lifespan, twenty years would pass in the blink of an eye."
"It’s not merely a matter of winning or losing."
All For One’s fist clenched tightly.
"You proved it, didn’t you? Through the Quirk Singularity Theory and its derivative, the ‘Third’ theory."
His red eyes bore into the child.
"Within One For All… the will of my brother, Yoichi, lives and breathes."
The child simply shrugged.
"Yeah, that’s right. A residual thought imprinted on the Quirk. That’s what exists within One For All."
"Exactly. So even if I were to artificially recreate ‘One For All,’ it would be nothing more than an empty shell."
Heat seeped into All For One’s voice.
"The soul that is Yoichi… exists only within the original ‘One For All’—in other words, inside All Might. That is the fact you demonstrated to me."
"Right. The one and only original."
"If ‘One For All’ self-destructs twenty years from now… then Yoichi will vanish along with it."
All For One’s face twisted grotesquely—a mixture of sorrow, rage, and an insatiable hunger.
"I cannot allow that."
He refused, his tone unyielding.
"It must be now. If not now—if All Might and that body are not still clinging to Yoichi…"
His voice trembled.
"Then I’ll never be able to properly play with my brother again!"
That perverse obsession, too relentless and horrifying to be dismissed as mere brotherly love, was the very force driving All For One—a primal longing deeper and darker than the ambition to rule the world.
The child burst into laughter, clutching his stomach as tears threatened to spill. It was a laughter of pure derision and incredulity.
"Ahahahaha! Seriously, what the hell!"
He giggled, still holding onto his belly.
"Even you should know, old man. Zero—the fundamentals of Singularity Theory."
Wiping the tears from his eyes, he continued,
"A Quirk perfected as a Singularity can only be countered or neutralized by the interference of a Singularity of equal magnitude. That’s the only way to overcome it."
The child’s words were as cold as a dagger.
"You know it too. Right now, you haven’t reached that stage yet. We haven’t finished the ‘Vessel’ yet."
All For One fell silent. It was true; he had yet to elevate his physical form and his Quirk to a perfect Singularity.
"So, to go into battle now means there’s a 99.9% chance you’ll lose. Your face might be smashed, or you might end up on life-support for the rest of your days. And yet, you still want to fight?"
"I know. All too well."
Even the specter of defeat could not deter him from his determined march.
"But there… my brother is there."
That one sentence—transcending logic, reason, and even survival instinct—silenced every counterargument.
The child stared at All For One for a moment before shaking his head and clicking his tongue.
"What a fool."
He laughed, a mix of genuine disbelief and a twisted amusement at the absurdity of the situation.
"Whether it’s brotherly love or mere stalking, it’s all just repulsive. You bluster on about ruling the world, yet in the end, you turn out to be nothing more than an overgrown, brother-obsessed runt. I’m disappointed, Demon King."
His tone was mocking, but his eyes shone with a mischievous delight.
The perfect equation he had devised—only to see it shattered by the unpredictable nature of human desire—was the ultimate entertainment for the child.
"Well, fine."
The child hopped down from the operating table, the cheerful clacking of his shoe heels ringing out. Clack.
"I won’t stop you. It’s your life—ruin it if you must."
After adjusting his attire to regain his gentlemanly poise, he turned toward the exit of the laboratory.
"I’m going now."
"………."
"These past few years have been fun. A really good way to while away the hours."
And that was the end.
The child never looked back. There were no farewell embraces, no tears of regret.
It was as if they had met like a passing breeze—here one day and gone the next.
He stepped out into the darkness without a second glance, and All For One did not stop him.
No, he couldn’t.
For that child was like the wind—belonging to no one, free to linger when he wished and to depart at his own whim.
Behind the child’s small figure, the sound of the laboratory’s automatic door closing echoed.
Hiss— Thud.
With that sound, All For One’s reminiscence came to an end.
This lore is pretty good too