One-Shot: Sisters

One-Shot: Forbidden Ritual

In an unknown place…

A vast hidden city, home to more than one hundred thousand souls. Humans, demi-beasts, youkai, and monsters lived in harmony, protected by their distance from civilization and the absence of conflict. It was a silent refuge from the chaos of the world.

Or at least… that's what they believed.

At the top of a mountain, on a rocky ledge that rose like a blade carved by the gods, a figure stood. The wind blew fiercely, tossing his messy white hair as if trying to rip away his thoughts. His red eyes, sharp as obsidian blades, watched the city with unnatural calm… like a demon about to claim what is his.

Two horns, red and black, crowned his forehead: the mark of his oni heritage.

He was no god.

Nor a savior.

He was a man with terrible determination.

Sengo—not yet known as the Demon Lord King Oni—descended slowly, his figure moving toward the heart of the city. To the inhabitants, he was just another traveler. A new face. An unknown name.

But to him… that city was an altar.

An ideal place for his purpose: the forbidden ritual.

When he reached the center, precisely where the land's spiritual energy was densest, a voice echoed in his mind. Soft. Feminine. Full of pain and longing.

"Daddy… are you sure about this?"

Kurumi.

The shadow trapped in his soul. A ghostly existence. A being that shouldn't have been born but still existed.

Sengo closed his eyes for a moment. His voice did not waver.

"Yes. I will activate the ritual… and I will sacrifice one hundred thousand lives to create an unnatural life. I'll do whatever it takes for you to be born with a physical body. I don't care if I'm branded. I don't care if the world calls me a monster. I promised you, Kurumi. And I will fulfill it."

Silence.

Then, Kurumi's voice trembled. Full of guilt, but also desire.

"Daddy… I… I know this is wrong… but I also… I want to live. I want to walk. Feel. Breathe. I want to exist, not as a shadow trapped inside you… but as someone real."

Sengo clenched his fists as the ground beneath him began to vibrate softly. The marks of the ritual, forming at that very moment, began to glow with a crimson light.

"Then prepare yourself, Kurumi… because what's coming… will change the world forever."

────── ✦ ────── •

The city buzzed with life.

Human children ran through stone alleys, laughing as they chased a ball made of rags. Women chatted near fountains, sharing rumors and laughter. Sturdy men carried boxes and barrels through the markets. Demi-beasts and monsters played cards on street corners, tossing coins onto improvised tables with grunts and laughter. Even the oldest youkai enjoyed tea beneath the trees, with narrowed eyes and expressions of peace.

It was a day like any other.

Until the ground began to glow.

First came a faint glimmer, dark red, imperceptible to the naked eye. But within seconds, that weak flicker became a sickly glow, spreading beneath everyone's feet. The inhabitants looked at the ground in confusion. Some screamed. Others tried to run.

Too late.

The ritual circle, now fully formed, had activated.

Archaic symbols emerged from the earth like open scars. They connected in serpentine lines that encircled every house, every street, every corner.

And then…

They fell.

Without a word. Without a scream.

One by one, the bodies collapsed. As if their souls had been ripped out all at once.

Silence was absolute.

────── ✦ ────── •

At the city's heart, where everything converged, a massive sphere of energy began to form.

It shone like a dark sun. It spun slowly, pulsing like an unborn heart.

Sengo, standing before the epicenter, watched the scene without blinking. His expression was stone. No guilt. No remorse. Only unbreakable resolve.

One hundred thousand lives… all reduced to one.

One single essence.

One life.

"Kurumi… is about to be born," he murmured, his voice a breath carried by the wind. "At last… I'll make it."

All around him, the bodies began to disintegrate, floating as motes of light, absorbed by the sphere that grew larger each second. A female shape began to form inside it. A childlike silhouette, latent, still faceless.

But then… something invaded him.

A thought.

A temptation.

A never-healed scar.

The curse of Gaia that wouldn't let him die.

But it didn't make him immortal in the usual sense.

When he died, his body didn't regenerate.

He didn't resurrect.

Time simply rewound, going back a few minutes—just before the fatal moment.

His body, dragged through temporal flow, returned to an immediate past where death hadn't occurred.

A constant return point.

A loop doomed to prevent his end.

A prison disguised as immortality.

Sengo stepped forward slowly. His hand reached toward the sphere.

And then he contaminated it.

Not out of malice.

Not out of arrogance.

Out of desperation.

His curse—bestowed by Gaia—seeped into the sphere, fusing with the energy of the one hundred thousand sacrificed souls.

He shouldn't have done it.

Black and silver bursts exploded like contained thunder. The sphere began to tremble. The figure inside it shuddered.

And then…

Crack.

An invisible fissure split it.

A division. A rupture.

Kurumi's essence, almost complete… fractured.

Two hearts beat at once inside the same mold.

Two souls. One essence. Opposing wills.

The ritual could no longer be stopped. The energy surged in every direction. The sphere expanded… and then exploded in a blinding wave of light.

When the glow faded, two girls lay in the center of the circle.

One with black hair in uneven twin tails like the hands of a clock, her right eye red and her left one something unnatural. Golden, with Roman numerals and clock hands marking 3 o'clock.

The other with white hair in symmetrical twin tails, her right eye red and her left one equally unnatural: an icy blue with Roman numerals, also marking 3 o'clock.

Sengo observed in silence. One eyebrow twitched.

This wasn't part of the plan.

It wasn't supposed to happen.

But it was too late.

What Kurumi and Shiro would one day believe—that their existence was split by a ritual anomaly—was only part of the truth.

The other part, the true cause, was the curse Sengo carried in his soul.

A curse that, in his desperation to be free, tainted the ritual and created an unplanned second daughter.

────── ✦ ────── •

Castle of the Oni King Yamato, Outer Gate Number: 2976

The sky was clear, with just a few clouds drifting like soft brushstrokes across the blue canvas. The midday breeze gently stirred the leaves of the red maples that surrounded the old castle, ancestral home of the Oni lineage.

On the wooden bridge that crossed a pond full of blooming lotuses, Sengo walked in silence.

His steps were slow. Almost ceremonial.

On each side, two small hands clung to his own.

Kurumi, now with a physical body of her own, skipped along in delight. Her laughter rang through the trees like a charming bell. Every jump made Sengo's arm lift from her childish enthusiasm.

Her eyes sparkled with an innocence she never had before. At last she was real. At last she could run, feel, live… beyond a spiritual prison.

At his other side, Shiro walked in silence. Her calm face and serene gaze contrasted completely with her sister. She didn't seem upset or uncomfortable. Just… distant. As if watching the world with eyes that had seen it all before.

They were like the reflection of the same moon on different waters.

Kurumi wore a pale green dress with floral details, her long black hair flowing behind her like a trail.

Shiro wore a light sky-blue dress, simple yet neat, her snow-white hair cascading down her back to her waist.

Sengo glanced at them, feeling a knot in his chest that was hard to untangle.

"So different… and yet, both are my daughters."

"One born from a promise… and the other from a mistake…"

Kurumi tugged his arm harder.

"Daddy! Did you see that!? A carp jumped out of the water!"

Sengo smiled faintly.

"Yes, I saw it."

Shiro looked toward the water too, saying nothing. Her face showed no surprise, but her fingers squeezed her father's hand more tightly. As if that simple contact was enough to anchor her to the present.

The three continued walking under the soft sunlight.

In the distance, crows cawed through the trees.

Kurumi talked endlessly. Shiro listened in silence. Sengo… simply walked with them both.

And for a fleeting moment, that cursed demon… allowed himself to feel at peace.

────── ✦ ────── •

Several days had passed since Sengo had spent time with Kurumi and Shiro. Walks, peaceful meals, starry nights, moments of joy.

But all things must end.

That morning, the sky was cloudy, covered by a faint mist slipping between the cherry trees in the inner garden. Sengo knelt before his daughters at the castle's main gate, a light travel bag slung over his shoulder.

"I'll be back soon," he said, gently ruffling both of their hair.

Kurumi, arms crossed, rolled her eyes.

"You always say that. I'm used to your disappearances. You're like the wind, Dad. You never stay still."

Sengo smiled.

"You lived inside me too long… you know how I am."

"Still, bring me something sweet," Kurumi muttered, turning her back with a barely visible smile.

Shiro, in contrast, simply watched him in silence. With her sky-blue dress and calm expression, she looked almost part of the scenery.

"We'll wait for you," she said simply. Few words, but full of sincerity.

Sengo leaned in and kissed their foreheads, one by one.

"I love you both."

And with that… he left.

────── ✦ ────── •

He had walked for hours, following paths that didn't exist on maps. The land grew barren, the breeze denser. As if the world knew where he was going… and what awaited him.

When he crossed a hill, a figure intercepted him.

A spear cut through the air. He dodged it easily, not even surprised.

"Hm. An unannounced attack?" Sengo muttered indifferently.

Before him, a young man in shining armor pointed his weapon. His face was youthful, but his eyes burned with restrained hatred.

"Sengo! Cursed demon! You've been condemned by the High Council of Little Garden. You are an enemy of the world!"

Sengo narrowed his eyes, unmoving.

"Ah, so they've found out."

"One hundred thousand lives! One hundred thousand souls sacrificed for a single whim! Your crime is unforgivable!"

The wind howled violently between them.

Sengo lowered his gaze, his fingers brushing the hilt of his katana. But he did not draw it.

"It wasn't a whim," he said softly.

"Silence! You performed a forbidden ritual! You killed innocents without mercy! Your existence is a curse upon this world!"

A heavy silence fell. Only the whispering wind and the echo of those words filled the air.

Sengo took a step forward.

"Then tell me… who decides which lives are worth sacrificing… and which are not?"

"Don't twist what you did!"

"I'm not seeking redemption," Sengo continued, his voice firm, now darker. "I don't even care about forgiveness. I did it knowing I'd be condemned. I would do it again… because from that sin, my daughters were born."

The warrior stepped back, doubting for the first time.

Sengo lifted his head. His red eyes burned like an infernal flame.

"Will you kill me… or just shout out my sins?"

Silence turned to tension.

A battle seemed inevitable.