Demon Slayer: I Got Reincarnated As Yoriichi

"You're dead… old ass," Tsunenari growled.

He charged forward, his kick aimed at the old man's chest, but the elder sidestepped effortlessly, grabbing Tsunenari's leg mid-swing. With a sharp twist, the old man hurled him into a cluster of trees.

Before Tsunenari could recover, the old man was already upon him, his fist racing toward Tsunenari's chest. Tsunenari barely managed to block it with a desperate kick, but the impact sent shockwaves through his body.

The elder shifted instantly, his fist grazing past Tsunenari's face, smashing a boulder behind him into shards. Tsunenari's eyes widened at the raw power.

"Damn it!"

Tsunenari retaliated with a sharp kick to the stomach, but the old man countered with a devastating punch to his jaw, launching him skyward.

In mid-air, before Tsunenari could even think, the old man appeared above him, driving a kick into his chin and sending him soaring higher.

"What the f— how can an old man be that strong? He must be a demon, but even demons aren't that strong. Who is this old man?" Tsunenari thought, blood dripping from his mouth as he tried to steady himself in mid-air.

As Tsunenari remains suspended in the air, the old man rushes toward him with blinding speed. In a desperate move, Tsunenari pulls a concealed knife from his clothes and slashes at the old man's eyes, blood spraying into the air. The old man stumbles, momentarily stunned.

Taking advantage, Tsunenari grabs the old man's face and hurls him toward the lake below with all his might. The elder crashes into the water, creating a massive splash.

Tsunenari lands smoothly on the ground, panting, his heart racing. The lake grows eerily still. Picking up his sword, he starts to retreat.

But then.

BOOM!

A deafening roar shakes the air. Tsunenari freezes, turning toward the lake.

The water erupts as the old man rises, now transformed, his body grotesquely expanding until he towers over the trees, water cascading down his monstrous frame.

Tsunenari trembles. "What?!! I thought he was innocent, no, I mean an old scum but still a human. And now, he has revealed his identity."

"Oi Oi Oi… What a shameless old hag. Do you still wanna fight and get a one-way ticket to hell?" taunts Tsunenari.

The elderly man, now transformed into a colossal demon, ignores his warning and charges forward with his massive form.

"WIND BREATHING, 1ST FORM: DUST WHIRLWIND CUTTER"

Tsunenari slashes the demon's left hand, but the demon remains unaffected and spews flames from its mouth at Tsunenari.

Their clash continues, Tsunenari weaving through the demon's brutal attacks while aiming precise blows. But with each strike, the demon's sheer resilience leaves him questioning.

How do I stop this monster?!

After a grueling and relentless battle, Tsunenari finally seizes an opening and decapitates the demon in one swift, powerful strike. The demon's massive body collapses with a thunderous crash, its severed head rolling away into the shadows.

Tsunenari is now exhausted after the long battle. He says, "Tch… I hate to accept it but it was the strongest demon I've ever encountered."

As he prepares to leave, he notices that something is ripping within the demon's body. Suddenly, a new demon emerges by tearing apart the old demon's body.

The new demon leaps 150 meters above the ground and appears in front of Tsunenari.

"WHAT!!!!!!! DID HE JUST REBIRTH?!!! ARE YOU KIDDING ME?!!! WHO IS THIS NEW DEMON NOW?!!!"

A fearsome new demon has emerged, sporting a striking appearance with six muscular arms, two menacing horns, and long, dark hair. Its piercing red eyes are so large, they nearly reach its ears, adding to the creature's ominous presence. One of its eyes bears the strange inscription "Lower 3", marking it as a demon of the lower third rank. Its intense physicality and imposing aura make it a truly terrifying sight to behold.

Tsunenari's blood runs cold. "A Twelve Kizuki… Lower Moon 3."

"KEKEKEKKEE…. HHUHHHUHHUHHHHH… HAHAHAHAHAA… HHAAAAHHHHAAAAHHHAAAA…" the demon laughs maniacally.

"Do you really think you defeat me so easily? It is such a shameful thing to be beaten by a kid like you. My name is Asmodeum. What's your name kid?" asked the demon, Asmodeus.

"Oh, a piece of sh*t like you wanna know my name before getting killed? Hahahahahahahaha…. How dare you talk to me like that? You moron."

Asmodeus vanishes, reappearing before Tsunenari and landing a brutal punch to his stomach, causing him to vomit blood. With a snarl, Asmodeus summons six blood spears, launching them at Tsunenari.

Tsunenari blocks with his sword, but Asmodeus' speed and strength overwhelm him. Sharp strikes tear through his body, blood pouring from countless wounds.

"Oh sh*t, if he keeps attacking me like this then I'll die soon. I am losing my consciousness… What's happening? I can't see correctly. My visions are getting blurred," thinks Tsunenari.

As he is about to be killed, some demon slayers come and help him from the Asmodeus. Some kakushis were also there and tried to heal him, but Asmodeus instantly killed all of them with his insane speed. Only one kakushi managed to escape but couldn't leave Tsunenari alone.

Asmodeus picked up a massive stone and struck Tsunenari's head with it. The blow was so powerful that Tsunenari immediately lost consciousness. Asmodeus then dragged him by the head and threw him into the lake.

The kakushi watches in horror, tears streaming down. Powerless, he retreats, leaving Tsunenari's fate sealed.

…

…he still has some consciousness remaining…

Tsunenari's mind flickers, still clinging to a faint sliver of consciousness.

In the vast lake, the cold water swallows him whole. Struggling to stay afloat, he feels his strength fade with each passing moment. His body sinks deeper, the pressure of the water dragging him toward an inescapable end. Despite his best efforts, his limbs grow heavy, his breaths shallow. The darkness creeps in, and he resigns himself to the inevitable, his heart weighed down with the finality of his defeat.

But then, a voice cuts through the despair.

"What are you doing, Tsunenari? Are you truly willing to die just because you faced a powerful demon? Death is easy, but remember your promise to me."

Tsunenari's eyes widen in shock as the figure of his father materializes in the water, his soul reaching out to him. The sight jolts him, stirring memories he had buried long ago. He remembers the promise he made as a child—when he was only six years old. He swore to his father that he would protect his siblings, that he would be their guardian, their strength.

Tears well up in Tsunenari's eyes, not from pain, but from the weight of his father's words, his unfulfilled promise.

I remember…

————————————————————————

I remember…

Six years ago.

My family was a joint family, bound together by blood and tradition. But it was a fragile bond, one that snapped under the strain of conflict. My uncles and aunts couldn't stand my mother. My father, the eldest sibling, tried his hardest to shield her from their hatred, but there was only so much he could do. It didn't matter how much he loved her, how much he fought for her. The rift was too deep.

So, we left. We moved away, far from the house that once held us together.

But even after we left, one of my aunts—her hatred for us burned so strong—refused to let my father return, no matter what. She'd let nothing stand in the way of her obsession with the family's property. And that's when it all went wrong.

Two years later, that woman… that b*tch… she took a step no one should ever take. She turned to black magic. She sacrificed the lives of two innocent children just to summon something, something monstrous.

I'll never forget that day.

It was 5 April 1948. The day everything changed. The day she called forth a being—dark as the night itself, with eyes glowing crimson red.

A being born of evil, and it came for us.

Day 1

My mother... she died. It was so sudden, so mysterious. One moment, she was there, and the next, she was gone. I couldn't even grasp what had happened.

Day 2

My younger brother... he was next. Just a child, so full of life, and yet, by the morning, he was gone. No explanation, no reason. Just silence where his laughter used to be.

Day 3

Then my sweet, innocent sister... she took her own life. No one knew why. She just... ended it. I never saw it coming.

Day 4

Another brother... taken. Killed by something. We don't even know what it was. It moved like a shadow, swift and merciless.

Day 5

My other sister... poisoned. The food was fine. There was no poison, yet somehow, she died. Slowly. Painfully.

Day 6

My father… had a dream. He spoke to someone. Someone who was all black, his eyes a piercing crimson. The figure was terrifying, yet… oddly, it seemed kind. He warned my father, told him that the curse would kill everyone in the house, that we needed to leave, or else it would be the end for us. He didn't want to hurt us.

But it was too late.

At 3 A.M., 12 April, 1948.

My father woke with a start. He picked up my one-year-old brother, his eyes wide with fear, and told me to leave. We ran. Twenty minutes, nonstop, until we reached the village's edge. I thought we were free.

But then… my father collapsed.

I rushed to him, terrified. But then, something horrifying happened. My father… dropped my brother. The little one, helpless in his arms. And then, with a horrific, unnatural force, my father attacked me.

His eyes turned red. I knew. I knew he was possessed.

I had no choice. I fought back, fought my own father, trying to protect my brother. For an hour, I fought against the man who had raised me, the man who loved me. I couldn't let him harm my brother.

In the end, I had to… I killed him. I had no other choice. I struck him with a boulder.

The pain… The grief… I couldn't stop crying. My father's lifeless body lay in front of me, and I had ended his life. But I had no choice.

I picked up my baby brother, Koji, holding him close, and I ran. But it didn't end there.

Some people came. They saw my father's body. They didn't understand. They accused me of murder. I was beaten. Brutally. And the kids… they mocked me. They called me a monster. I was imprisoned for two months. Two months of torment.

The world… turned against me. They blamed me for everything. My own family's deaths.

I tried to hold on. I tried to keep the part of me that was still innocent, still human.

But how could I?

Every day, the pain crushed me, twisted me. And in the end, I lost myself. I lost everything that once made me happy.

I became a shadow. A monster. Forever haunted by the memories of my family... and the fate I couldn't escape.

I deserve to die. I shouldn't be here, still breathing, still living.

Now, I understand why Hanako-san hated me. She couldn't even stand to look at me. How could she? I was nothing but a reminder of everything I lost, of the monster I became. I hated Hajime-san. I hated Yamamoto-san. But more than anything, I hope they can forgive me.

Forgive me, Koji. I'm so sorry. I couldn't protect you... I failed. I couldn't keep my promise.

I should've died with them.

But then, something shifts.

I still have my katana. It's still there. I can still fight. I can still make this right. Maybe... just maybe, I can end this. I can win.

As Asmodeus savored the remains of the fallen demon slayers and kakushis, his eyes caught sight of something that made his blood run cold. Tsunenari was coming.

The air itself seemed to crack and bend as Tsunenari tore through the lake, moving faster than any mortal could comprehend. His speed was beyond hypersonic, a blur of destruction that left a trail of shattered earth and splintered trees in his wake. Every step he took shook the ground beneath him, every movement sent shockwaves through the air.

Asmodeus, who had previously defeated Tsunenari, stands ready to face him once again. Both warriors are poised for the ultimate showdown, their eyes locked in a fierce gaze, as they prepare to engage in an epic battle.

With a roar that split the sky, Asmodeus lunged, his six arms flailing wildly in every direction. His strength was monstrous, but Tsunenari was faster. With expert precision, he dodged the demon's deadly strikes, his movements a blur of fluid grace.

Then, with a swift strike, Tsunenari slammed into Asmodeus's back, the impact echoing through the battlefield.

The two clashed for thirty intense minutes, neither willing to yield.

But then, in a sudden, heart-stopping moment, Asmodeus gained the upper hand. His spear pierced Tsunenari's side, and the warrior stumbled, pain searing through him. Blood poured from the wound, but Tsunenari wasn't finished yet.

With a snarl, he drew his katana in one fluid motion, his hands steady despite the blood dripping from his wounds. In an instant, he closed the distance between them and swung with all his remaining strength.

In one swift motion, he drew his katana and, with a fierce slash, severed Asmodeus's head, ending the battle once and for all.