Demon Lord reborn as The Hero's Child

Kōya knew exactly how to wield demonic power.

At least, the ghost living inside his mind thought he did.

He distinctly remembered the intoxicating, omnipotent feeling of it. He remembered abyssal mana rushing through his veins like a vast, violent river, answering his darkest will without a single moment of hesitation. He remembered the physical sensation of pure, suffocating darkness gathering around his hands, heavy enough to bend the air itself. He remembered legendary, enchanted weapons being torn apart by a single, lazy strike of his fingers, and massive, glittering armies collapsing into dust beneath a sheer atmospheric pressure that ordinary mortals could not even begin to comprehend.

For centuries, he had commanded that apocalyptic power as naturally as a mortal drew breath.

Now, he was sitting on a woven rug on the wooden floor.

He stared down at his tiny, pudgy hands.

They were soft. They were impossibly small. They were entirely, humiliatingly useless.

Kōya frowned, a deeply serious expression that looked entirely absurd on an infant’s round face.

He closed his eyes, shutting out the warm sunlight filtering through the cottage window, and violently commanded his memory to summon the sensation of his ancient mana.

Nothing.

He concentrated harder, grinding his toothless gums together.

Still absolutely nothing.

*Come on.*

He tried again, diving into the deepest, darkest trenches of his soul. He vividly imagined the suffocating darkness gathering inside his core. He pictured the rushing flow of abyssal mana moving up through his chest and channeling toward his right hand. He meticulously recreated the ancient incantations in his mind, the visceral feeling, the exact atmospheric pressure he used to create before annihilating a mountain.

Nothing happened. The air in the quiet room did not chill. The shadows on the wall did not lengthen.

Kōya opened his eyes, glaring at the floor.

His tiny, soft fingers were still exactly the same.

He clenched them into pathetic little fists.

Nothing.

He tried one last time. This time, he threw his pride away and pushed with absolutely everything his new, fragile physical form could endure.

His little cheeks puffed out. His face turned a dangerous shade of crimson from the sheer, trembling effort of trying to force a supreme demonic aura through the undeveloped mana veins of a human newborn.

Suddenly, a strange, incredibly faint pressure appeared deep inside his chest.

Kōya’s large eyes widened.

*There!*

He had actually felt something. It was microscopic, a mere droplet in the ocean of what he used to possess, but it was real.

He locked his formidable concentration onto it like a starving predator.

The faint pressure moved slightly, warming his sternum.

Then, like a candle blown out by a draft, it completely disappeared.

Kōya stared at his hands in absolute, soul-crushing disbelief.

That was it? After centuries of undisputed supremacy, after commanding legions of warlords and shattering the sky, that pathetic, microscopic spark was all his new physical body could produce?

He tried once more, desperate.

Nothing.

His small, fragile body simply did not have the physical capacity to hold mana yet. Even worse, the phantom connection to his past meant he had absolutely no mechanical control over what little latent energy actually existed inside his new blood.

Kōya lowered his heavy head, resting his chin on his chest.

He was Raizen Kurogane.

The Supreme Demon Lord. The Destruction King. The absolute nightmare of the living world.

At least, that was the man he explicitly remembered being.

And yet, sitting here on a soft rug, he could not even make a single spark of darkness appear to warm his own hands.

He slowly lifted his gaze toward the kitchen, where a tall man was sitting comfortably at a wooden table, repairing a leather harness.

Seiya Amane.

The legendary Hero. The man wielding the holy sword. The man who had driven a blade of blinding light through his chest and ended his centuries of rule.

Kōya’s tiny, innocent eyes narrowed into slits of pure, calculated malice.

If he could not use his apocalyptic magic, then he would simply have to find another, more physical way to execute his vengeance.

His very first attempt was simple, brutal, and entirely opportunistic.

Kōya waited patiently on the floor until Seiya stood up and walked past him carrying a bundle of firewood.

As the Hero’s leg brushed past the rug, Kōya lunged. He reached out with both tiny hands, grabbed his father’s pant leg in a death grip, opened his mouth, and bit down as hard as his jaw would allow.

Seiya stopped mid-stride.

”...Kōya?”

Kōya clamped his jaw tighter, attempting to draw the blood of his murderer. He wanted to hear the Hero scream.

Seiya looked down, shifting the firewood in his arms to see the tiny infant viciously attached to his calf.

For a long, quiet moment, neither of them moved. The Supreme Demon Lord gnawing furiously on the Hero’s leg.

Then, Seiya laughed.

It wasn’t a mocking laugh. It was a deep, warm, entirely genuine sound of fatherly amusement.

”Are you hungry, little guy?”

Kōya immediately released the fabric, disgusted.

He tipped his head back and stared up at the towering man with complete, unadulterated irritation.

Seiya casually set the firewood down, crouched to the floor, and smiled warmly, his golden eyes completely devoid of the killing intent they had once shared on the battlefield.

”You wanted my attention, huh?”

Kōya turned his face away, refusing to make eye contact with his assassin.

Seiya gently reached out and picked him up, lifting him under the arms.

Kōya immediately began struggling, thrashing his little legs and pushing against the man’s iron-hard chest.

”Hey, hey. What’s wrong?” Seiya asked softly, bouncing him gently.

Kōya pushed harder, his tiny hands pressing furiously against the exact spot where the Hero’s armor used to be.

Seiya only laughed again, a sound that grated against every demonic nerve Kōya possessed.

”Wow, you’ve gotten strong.”

Kōya glared at him, his internal monologue screaming.

*Strong?*

He had once crushed entire vanguards by clenching his fist. He had collapsed fortresses with a single word. Now, his murderer was genuinely impressed because he could push his tiny, useless hands against a man’s chest without immediately exhausting himself.

This was a psychological torture worse than hell.

Seiya carried him effortlessly across the room, walking over to where Mizuki was slicing vegetables at the counter.

”He’s angry with me again,” Seiya reported, sounding more amused than concerned.

Mizuki looked over her shoulder, a soft, maternal smile gracing her lips. ”Maybe you bothered him.”

”I didn’t do anything!” Seiya protested defensively.

”You probably did,” Mizuki replied smoothly.

”I only picked him up. He was biting my leg.”

Kōya stared at the two of them.

They were talking about him—about the Supreme Demon Lord—as if he were a mindless pet that wasn’t currently plotting their violent demise.

He aggressively folded his tiny arms across his chest, scowling deeply.

Mizuki noticed the posture and chuckled. ”Look at him.”

Seiya looked down at the infant in his arms.

Kōya’s expression was as dark, imposing, and serious as he could possibly make it with a face composed entirely of baby fat.

Seiya burst out laughing, completely unaffected by the sheer killing intent radiating from his son.

Kōya’s scowl deepened, his irritation reaching astronomical new heights.

A few days later, Kōya decided to try a different tactical approach.

This time, he waited until Seiya was sitting quietly on a heavy wooden chair near the hearth, entirely focused on reading a weathered map.

Kōya army-crawled across the floorboards, utilizing the absolute stealth he had once used to bypass elven wards.

Seiya did not notice. His guard was entirely, pathetically down.

Kōya reached the chair. He placed both of his soft hands flat against the thick wooden leg, braced his knees against the floor, and prepared to topple the Hero backward into the stone hearth.

He pushed.

Absolutely nothing happened. The heavy oak chair did not even vibrate.

He gritted his gums and pushed harder.

The chair shifted perhaps a fraction of a millimeter.

Kōya’s eyes sharpened with dark determination. He gathered every single ounce of physical strength his new body possessed. He pushed again, throwing his entire weight into his arms.

The chair gave a loud, scraping screech across the wooden floor.

Seiya lowered the map and looked down.

”What are you doing down there?”

Kōya ignored him, digging his toes in and continuing to push.

The chair moved another agonizing two centimeters.

Seiya stared at him in utter bewilderment.

Then, a slow, highly annoying smile spread across the Hero’s face.

”Are you... trying to move my chair, Kōya?”

Kōya stopped pushing, panting slightly from the exertion.

Seiya leaned forward, resting his elbows on his knees, looking into Kōya’s dark, serious eyes.

”Why?”

Kōya looked right back at him, his mind perfectly clear.

*Because I want you dead. Because I want to shatter your spine against those stones for what you did to my empire.*

The words existed with absolute, terrifying clarity inside Kōya’s ancient mind.

But his infant vocal cords, utterly undeveloped and useless, could not physically form the complex syllables of vengeance.

Instead, as he opened his mouth to deliver his death threat, he made a sharp, irritated baby sound.

”Ba!”

Seiya blinked, completely taken aback.

Then, his smile widened into a massive, glowing beam of paternal joy.

”Ba?”

Kōya’s face darkened with absolute horror.

*No.*

”Did you just say ’ba’?” Seiya gasped, looking around the room as if he had just witnessed a miracle.

*No! I was threatening your life!*

”Ba!” Seiya repeated encouragingly, leaning closer.

Kōya furiously slapped his tiny hand against the floorboards in protest.

Seiya laughed, the sound booming in the small cottage.

Mizuki, who had been quietly preparing food nearby, glanced over with a fond smile.

”What happened?”

”Your son is trying to tell me something,” Seiya announced proudly. ”He said ’ba’.”

Mizuki wiped her hands on her apron and looked at Kōya.

Kōya pointed an accusing, trembling finger directly at Seiya, his face a mask of pure fury.

Mizuki sighed, her eyes filled with amusement. ”He doesn’t seem to like you very much, Seiya.”

Seiya placed a dramatic hand over his heart, feigning a mortal wound. ”That hurts.”

Kōya stared at him coldly.

*Good.*

Seiya suddenly leaned off the chair, bringing his face dangerously close to Kōya’s level.

”Maybe if I make him laugh, he’ll finally forgive me.”

Kōya’s eyes widened in alarm.

Seiya puffed out his cheeks, filling them with air until he looked like a stranded fish.

Kōya stared, absolutely stone-faced, projecting his superior demonic dignity.

Seiya made a ridiculous, highly exaggerated face, stretching his mouth wide.

Kōya continued staring, refusing to yield a single inch.

Seiya crossed his eyes, sticking his tongue out.

Nothing. Not even a blink from the Destruction King.

Seiya wiggled his ears, a bizarre physical trait Kōya hadn’t known the Hero possessed.

Kōya’s stoic expression remained entirely unchanged, though his internal monologue was questioning the intelligence of the man who had defeated him.

Determined, Seiya made an exaggerated, rumbling growling sound, widening his eyes and shaking his head like a wet dog.

Kōya’s lips twitched.

He immediately clamped his mouth shut, horrified.

*No.* He would not laugh. He was the Supreme Demon Lord. He did not find this pathetic display of human buffoonery amusing.

Seeing the crack in the armor, Seiya doubled down. He tried again.

This time, he combined the crossed eyes, the puffed cheeks, and a high-pitched, ridiculous squeak that was so fundamentally absurd, so utterly devoid of the Hero’s legendary dignity, that Kōya’s developing infant brain could not process the contradiction.

A tiny, bright laugh escaped Kōya’s lips.

Seiya froze in triumph.

Mizuki smiled softly from the kitchen. ”There.”

Seiya looked victorious, throwing his hands in the air. ”He laughed! I knew I could break him!”

Kōya immediately looked away, staring at the floorboards, a profound, sickening sense of defeat washing over him.

He hated that man.

He hated him for destroying his kingdom. He hated him for ending his life.

So why, against every fiber of his ancient, vengeful soul... had he laughed?

As the slow, agonizing months passed, Kōya continued trying to aggressively understand and command his new, fragile body.

He tried summoning his demonic power again and again, in the dead of night, in the early mornings, whenever he was left alone.

Every single attempt ended the exact same, humiliating way.

Sometimes, if the room was cold enough, he could feel the absolute smallest, microscopic trace of mana deep in his marrow.

Sometimes, he felt absolutely nothing at all, as if he were entirely mundane.

He eventually, bitterly understood the fundamental problem.

His ancient knowledge had miraculously survived the cycle of reincarnation.

His overwhelming power had not.

Or perhaps, he theorized, the power was still there, locked away, buried somewhere infinitely deep beyond the physiological limits of this tiny, undeveloped human body. If a newborn tried to channel the mana of a Supreme Demon Lord, their heart would likely detonate. The body was protecting itself by refusing the connection.

Either way, he would have to wait. He would have to grow.

That profoundly frustrated him.

Raizen Kurogane had never been a patient man.

Kōya Amane was not patient either.

But there was absolutely nothing he could do about it.

So, he started looking for other, pettier methods of warfare.

When Seiya was sleeping exhausted on the floor after a long day of cutting timber, Kōya once crawled entirely across the room, stood up using the wall for balance, and stomped his tiny heel directly onto the bridge of Seiya’s foot.

Seiya woke up immediately, his combat instincts flaring.

”What was that?” the Hero demanded, sitting up and scanning the room for assassins.

Kōya had already dropped back to the floor, sitting innocently, staring blankly up at the wooden ceiling.

Seiya looked down at the tiny boy sitting beside his foot.

”Kōya.”

Silence.

”Did you just step on me?”

Kōya slowly turned his face away, offering the Hero his profile.

Seiya sighed, rubbing his foot, a small smile breaking through his exhaustion. ”You did, didn’t you.”

Kōya immediately began crawling away as quickly as his arms and legs could carry him.

Seiya chuckled, getting to his hands and knees to follow him. ”Oh no, you don’t. Come back here.”

Kōya crawled faster, his heart pounding with an entirely new kind of adrenaline.

For the very first time in his exceptionally long, violent life, Kōya discovered that successfully retreating from a legendary Hero could be extremely difficult when you were still mastering the basic mechanics of crawling.

One quiet afternoon, Kōya found a thin, sturdy wooden stick resting near the hearth.

It was nothing inherently special. It was simply a fallen oak branch, stripped of its bark, that Seiya had brought inside with some kindling and forgotten to throw into the fire.

Kōya picked it up. His small fingers wrapped around the wood. It felt balanced. It felt like a weapon.

He looked across the room at Seiya.

Then down at the stick.

Then back at Seiya.

The Hero was currently kneeling near the window, his back completely turned, thoroughly distracted by repairing a torn window shutter.

Kōya slowly raised the stick.

He moved toward his target. Absolute silence.

One unsteady step.

Then another.

He closed the distance. He lifted the stick high above his head, aiming directly for the back of Seiya’s knee, intending to strike the nerve cluster he knew lay beneath the skin.

Seiya, sensing movement, began to turn. ”Kōya?”

Kōya swung with everything he had.

The stick stopped dead in midair, mere inches from the Hero’s leg.

Kōya blinked, trying to pull it back. It wouldn’t budge.

A thick, dense ribbon of pure water had wrapped itself tightly around the wood, freezing it perfectly in space.

Kōya stared at the unnatural water, his breath catching.

Mizuki stood several steps away near the kitchen basin.

She had not raised her voice. She had not shouted a warning. She simply stood there, watching him with an expression that was entirely unreadable.

With a slight, effortless flick of her wrist, the ribbon of water pulled the stick gently but firmly from Kōya’s tiny hands, carrying it through the air and placing it quietly on the high table, completely out of his reach.

Kōya slowly turned his head and looked at her, his ancient instincts screaming a warning. Her magic was flawless. Absolute.

Mizuki wiped her hands on a cloth and walked slowly toward him.

She crouched down until she was eye-level with the boy.

”I know what you want to do,” she said, her voice soft, but carrying an underlying weight that commanded absolute attention.

Kōya froze entirely.

For a terrifying, suffocating moment, he wondered if she actually knew.

Could she see the bloody memories locked inside his infant mind?

Could her absolute protection magic somehow read souls? Did she understand exactly who he had been? Did she know she was raising the monster who had almost ended the world?

Then, Mizuki reached out and gently, warmly touched the top of his head, her fingers stroking his soft hair.

”But you see, Kōya... your father loves you very much.”

Kōya looked past her shoulder toward Seiya.

Seiya had turned fully around now. He had seen the stick. He had seen the strike.

But the Hero had not become angry. He had not drawn a weapon. He had not yelled. He was simply sitting on the floor, watching his son.

There was absolutely no hatred in his golden eyes.

No suspicion.

No fear.

Only a deep, profound concern for why his child was so angry.

Kōya looked away, unable to bear the weight of that golden gaze.

Mizuki gently slid her arms under him and picked him up, holding him securely against her chest.

”You don’t have to like him yet,” she whispered softly into his ear, understanding the inexplicable rage of a child in a way only a mother could.

Kōya remained dead silent, resting his chin on her collarbone.

”But you must not hurt him,” she added, the soft command vibrating against his chest.

She carried him away from the window, toward the kitchen table.

Kōya rested his heavy head against her shoulder, staring blankly at the floorboards.

He did not understand her at all.

Or perhaps, he thought with a sinking, terrifying realization, he understood her far too well.

After the incident with the stick, Kōya changed his tactics. He stopped actively plotting.

Instead, he began watching.

That was something he had rarely ever done as Raizen Kurogane.

As a Supreme Demon Lord, he had always been the center of the universe. He had always been the one people watched, analyzed, and feared. He acted, and the world reacted.

Now, trapped in the corner of a quiet room, he watched everyone else.

He watched Mizuki closely in the early mornings.

She would wake long before the sun, slipping quietly from the bed. She prepared food with practiced grace, cleaned the small house, and checked on him constantly.

If Kōya cried out from a nightmare of his past life, she came running in the dark, her magic flaring protectively.

If he was hungry, she fed him immediately, without complaint.

If he fell asleep somewhere uncomfortable, playing on the hard floor, she gently carried him to his warm bed, tucking the blankets tightly around him.

If he became restless or colicky, she held him against her chest, rocking him for hours until he finally calmed down.

There was absolutely no political calculation behind any of her actions.

There was no hidden motive. No grand bargain being struck. No expectation of future loyalty.

She simply, fiercely loved him.

Kōya did not know what to do with that. It broke every rule of the brutal reality he had known for centuries.

Seiya, on the other hand, was entirely different.

The legendary Hero was shockingly clumsy in domestic life. He dropped plates. He sometimes burned their food while distracted. He once spent nearly an hour trying to meticulously repair a broken wooden toy, only to accidentally snap it in half, making it significantly worse.

But whenever Kōya looked across the room at him, Seiya smiled. A genuine, unguarded smile.

Whenever Kōya crawled toward him, Seiya immediately dropped whatever he was doing and picked him up.

Whenever Kōya managed to make a new, coherent sound, Seiya celebrated the event as if his son had just accomplished something extraordinary, like slaying a dragon.

And when Kōya finally began trying to stand on his own two feet, Seiya became absolutely impossible to manage.

Kōya crawled to the low wooden table. He grabbed the edge with both hands.

His tiny legs trembled violently under his own weight.

He gritted his teeth and pulled himself upward.

For a single, triumphant second, he stood.

Then, his undeveloped knees gave way completely.

He fell backward.

Before his head could strike the hard wooden floor, large, calloused hands caught him flawlessly in midair.

”Got you,” Seiya whispered, kneeling right behind him.

Kōya stared up at him, breathless.

Seiya gently held him upright, setting his feet back on the floor. ”Again?”

Kōya looked down at his shaking legs. He hated the weakness. He had to conquer it.

He tried again. He let go of the table.

He fell almost immediately.

Seiya caught him again.

And again.

And again.

Kōya became intensely irritated. He didn’t want the Hero’s help. He wanted to stand under his own sovereign power.

He violently pushed Seiya’s large, protective hands away from his waist.

”I can do it.”

The complex sentence existed perfectly in his ancient mind, but the words came out of his infant mouth horribly mangled.

”B... I... do...”

Seiya didn’t laugh. He smiled, a look of profound, unwavering patience.

”That’s right, Kōya. You can do it. Try again. I’m right here.”

Kōya turned back to the table. He grabbed the edge.

He pulled himself up, forcing his mana-less muscles to obey his absolute will.

His legs shook violently.

He let go of the table.

He remained standing for three agonizing seconds.

Then four.

Then five.

He slowly turned his head and looked at Seiya.

Seiya was beaming, his golden eyes shining with an immense, quiet pride. He hadn’t reached out. He had simply trusted him to stand.

Kōya immediately looked away, staring at the wall.

But something deep inside the dark, untouchable core of his soul had shifted.

Very, very slightly.

Eventually, through sheer demonic willpower and relentless stubbornness, Kōya learned to walk.

His first steps were unsteady, drunken lurches across the floorboards, but they granted him an entirely new level of autonomy.

The quiet world that had once seemed enormous from the floor became even larger and more complex when viewed from an upright, albeit very short, perspective.

The small house had dark corners he had never noticed. The windows were much higher than he expected, showing him glimpses of rolling green hills. The wooden shelves were filled with strange, fascinating things he still could not reach.

There were sounds outside in the village that he did not recognize—the clinking of a blacksmith, the bleating of sheep.

And there were doors inside the house he had never been allowed to open.

One late afternoon, while wandering aimlessly through the quiet house while Mizuki washed clothes outside, Kōya found one of them.

It was a small, heavy wooden door situated at the very end of a narrow, shadowed hallway.

He placed his small hands flat against the wood and pushed with his body weight.

The latch had not been secured. The heavy door creaked open.

Kōya stepped inside.

Motes of dust floated lazily through a single, thin beam of golden sunlight piercing through a high, dirty window.

The room was not particularly large. It looked like a mundane storage closet that had slowly, organically evolved into a chaotic library.

Tall, sagging wooden shelves covered three of the walls. Heavy, leather-bound books were stacked haphazardly on the floor in uneven towers.

But it wasn’t just books.

There were old, blood-stained clothes hanging from rusted wooden hooks.

A few battered, dented pieces of high-tier magical armor rested against one wall.

There were worn leather boots. Heavy traveling backpacks. Old, enchanted belts. Coils of climbing rope. Rolled-up maps of the Demon Realm.

And several legendary pieces of adventurer equipment that Kōya instantly recognized from his past life.

Kōya stopped dead in the center of the room.

His wide eyes moved slowly from one object to another.

This was not simply a storage room.

Seiya and Mizuki had brought the physical remnants of their old, violent life with them into hiding. This was the graveyard of the Hero’s party.

Kōya walked deeper into the shadowed room, drawn to the towering shelves.

His tiny fingers reached out, brushing against the cracked spine of a massive book.

Then another.

Then another.

Most of the faded, embossed titles meant absolutely nothing to him.

He could recognize the fundamental shapes of the letters. He knew it was human script. But the words themselves did not immediately translate into meaning in his infant brain.

That profoundly surprised him.

He remembered countless languages. He remembered deciphering ancient, cursed inscriptions in the dark ruins of the abyss. He remembered fluently reading complex political documents written centuries before Seiya Amane was even born.

Yet now, staring at a shelf, he could not properly read a simple historical text. His brain simply hadn’t developed the neural pathways to process the translation.

Kōya grabbed the spine of one book on the lowest shelf and pulled.

It was significantly heavier than he expected.

It slipped from his tiny grip.

He dropped it.

The massive tome landed flat on the wooden floor with a loud, resounding *thump*, kicking up a cloud of ancient dust.

Kōya stared at it, coughing slightly.

Then, he dropped to his knees and picked it up again, struggling with the weight.

He turned the heavy book over to look at the front cover.

There was a name written across the dark leather in faded gold lettering.

*Raizen Kurogane.*

Kōya completely stopped breathing.

Directly below the name was another, larger title, etched in aggressive red ink.

*Raizen Kurogane: The Destruction King.*

He stared at the words, his heart hammering a frantic, terrifying rhythm against his small ribs.

He knew that name.

He knew that face, embossed in shadow on the leather.

He knew the terrifying, apocalyptic man described by those letters.

Because that man had been him.

With trembling hands, Kōya opened the heavy cover.

The very first page contained a stark, charcoal drawing.

A towering, dark figure stood upon a hill, looking down over a burning battlefield. The artist had drawn him as a literal monster—faceless, radiating pure, suffocating darkness.

Around him were piles of dead human soldiers. Burning, ruined buildings. Broken, shattered weapons.

The next page showed chained prisoners being dragged away into the dark by grotesque, laughing demons.

Kōya’s tiny fingers tightened fiercely around the edges of the book, crinkling the old parchment.

He forced himself to continue reading.

Or, at least, he tried to.

The black letters seemed to move and swim across the page. He understood some of the simpler words. *Death. Fire. Blood. Demon.* Others completely escaped his developing comprehension.

His previous, vast knowledge was like a grand, stone bridge that had been violently broken in half. He could see the other side clearly, but he could no longer cross the chasm to reach it.

He turned another heavy page, staring at an illustration of a village being reduced to ash.

A shadow suddenly fell across the book, blocking the beam of sunlight.

”Kōya?”

He gasped, looking up quickly.

Mizuki stood quietly in the doorway.

She glanced down at the open book in his lap.

Her soft expression changed slightly, a flicker of deep, complicated sorrow passing through her eyes.

”You found that?” she asked softly.

Kōya held the book tightly against his chest, defensive.

Mizuki walked slowly over to him, her dress rustling in the quiet room.

”It’s getting late, little one.”

She knelt down and gently took the heavy book from his small hands.

Kōya reached for it, a sudden spike of panic hitting him. ”No.”

Mizuki smiled, a sad, knowing smile, and closed the cover, hiding the Destruction King away.

”We’ll read it tomorrow,” she promised quietly.

Kōya protested, making an angry sound, but she effortlessly picked him up, resting him against her hip.

He looked back over her shoulder at the dusty shelves as she carried him away from the room.

The book disappeared behind the heavy wooden door as she closed it with a soft click.

But its title remained burning vividly in his mind, branded into his thoughts.

*Raizen Kurogane. The Destruction King.*

The very next morning, Kōya woke exceptionally early.

The moment he saw Mizuki walk into the main room, he crawled rapidly toward her and pointed a demanding finger directly toward the narrow hallway.

Mizuki stopped, looking down at him. ”What is it, Kōya?”

Kōya pointed again, his expression grave.

”The room?” she guessed.

He nodded firmly.

”The books?”

He nodded again.

Mizuki sighed softly, a complex smile touching her lips. ”You want to go back in there?”

Kōya nodded, entirely unyielding.

She picked him up and carried him down the hall.

This time, they sat together on the floor of the dusty library. She retrieved the massive book from the shelf and opened it across her lap.

Kōya sat closely beside her, his eyes locked on the pages.

Mizuki took a deep breath, and began reading aloud.

”The story of Raizen Kurogane is one that has been passed down by terrified adventurers for generations...”

Kōya listened, perfectly still.

At first, he was remarkably calm. He knew his own history.

But then, he heard the specific, visceral stories.

Human villages completely destroyed in the dead of night. Innocent people slaughtered by the thousands. Families violently separated. Famous adventurers disappearing into the abyssal torture chambers of the capital, never to return.

Trains of weeping slaves being marched in chains toward the hostile territories controlled by his demonic vassals.

People praying on their knees in burning churches for Heroes to come save them.

People screaming and cursing the name of Raizen Kurogane as they died.

Kōya’s expression slowly, painfully changed.

”...Raizen was believed to be solely responsible for countless, apocalyptic wars between the realms of humans and demons...”

Mizuki continued reading, her voice steady but laced with a profound sadness.

Kōya looked down at his lap, his tiny hands trembling.

He vividly remembered those wars.

He remembered the endless, exhausting war councils. He remembered the arrogant, bloodthirsty generals. He remembered the desperate political decisions made to keep his own fractured empire from collapsing into civil war.

He remembered complex, agonizing things that had never once appeared in this human book.

But the book was not necessarily lying.

That was the terrifying realization that truly bothered him.

The human adventurers who wrote this history had seen innocent people die. They had seen families lose absolutely everything to the flames. They had watched their loved ones being taken away in chains. They had fought his terrifying demons in the mud and the blood. They had seen the devastating, indiscriminate fury of Raizen’s armies.

Of course they hated him. They had every right to hate him.

But they had not known *everything*.

They had not stood in the cold, shadowed throne rooms where impossible decisions were made. They had not seen the treacherous, invisible forces and rebellious Peers moving behind the curtains of the wars. They had not known what Raizen had known—that to show weakness for a single second meant the eradication of his entire race.

They had only ever seen the horrific, bloody consequences of his survival.

Kōya suddenly reached out and slapped his small hand flat against the page, interrupting her.

”No.”

Mizuki stopped reading.

She looked down at him, surprised. ”What is it, Kōya?”

Kōya pointed fiercely at the illustration of the faceless monster on the page.

”No.”

Mizuki tilted her head, her long hair falling over her shoulder. ”You don’t like the story?”

Kōya aggressively shook his head.

He knew exactly what he wanted to say.

*That wasn’t everything. That wasn’t who I was. I was a king, not a monster. I made those choices because I had to!*

He desperately wanted to explain. He wanted to tell this gentle, loving woman that the terrifying man painted in this book was not the complete truth of his soul.

But he could not.

His vocabulary was still tragically incomplete. His physical ability to speak was nonexistent. His memories were violently tangled with a mortal life that had definitively ended.

He was trapped in the silence.

Mizuki looked at his frustrated, agonizing expression.

She gently reached out and touched his hair, her fingers cool and soothing.

”It’s only one story, Kōya,” she said softly.

Kōya looked up at her, his eyes wide, shining with unshed tears.

She continued, her voice filled with a profound, ancient wisdom.

”There are always different sides to a story. History is only written by the people who survive to hold the pen.”

Kōya’s breath caught in his throat. His eyes widened slightly, staring at the woman who had helped kill him.

Mizuki smiled, a warm, forgiving light in her eyes. ”Maybe, one day when you’re older... you’ll understand all of them.”

Kōya looked slowly back down at the book.

For the very first time since his inexplicable reincarnation, he did not feel a spike of arrogant anger simply because the humans hated Raizen Kurogane.

He felt something infinitely more complicated, and infinitely heavier.

Regret.

Profound confusion.

And a crushing, undeniable sense of responsibility.

He had been Raizen Kurogane. He could not erase that bloody legacy. He could not pretend the millions of dead had never existed. And he could no longer blindly blame every person who had suffered because of his command.

But neither could he simply accept that the monstrous history written in this dusty book was the complete, absolute truth of his existence.

Kōya closed his eyes, inhaling the scent of old paper and dust.

His previous, violent life was completely behind him.

His dark memories remained. His catastrophic mistakes remained.

But his new life had only just begun.

He slowly opened his eyes and looked down at his small, soft hands resting on the parchment.

The hands of an innocent child.

Not the hands of the Supreme Demon Lord.

Not yet.

And perhaps... never again.

He still desperately wanted his dark powers back. He still wanted concrete answers about the universe. He still did not know exactly *why* he had been given a second chance at life.

But one terrifying, exhilarating thing was finally becoming clear.

This time, he would have to learn absolutely everything again.

How to walk without falling.

How to speak without commanding.

How to read without prejudice.

How to eventually control his devastating mana without letting it consume him.

How to truly understand people, rather than simply ruling them.

How to live.

And perhaps, most daunting of all... how to become someone entirely other than Raizen Kurogane.

Kōya looked up at his mother, watching the gentle way she smiled at him.

Then, he turned his head and looked through the open doorway. Down the hall, he could see Seiya standing outside in the yard, bathed in the morning sun.

His father—the legendary Hero who had slain him—was currently struggling to chop a particularly stubborn piece of firewood, making an expression of absolute, ridiculous concentration over a task that definitely did not require that much effort.

Kōya watched the Hero for a long while, a strange, complicated warmth blooming in his chest.

Then, he looked back down at the heavy book.

A Supreme Demon Lord had lived once. A Destruction King had burned the world.

That violent life had definitively ended in blood and ash.

Now, there was only Kōya Amane.

And this time, the long, unwritten path ahead belonged entirely to him.