The Greatest Assassin Gets Reincarnated in Tensura

The day had started like any other for Yuuki Kagurazaka. He walked through the bustling streets, a bright smile on his face, radiating boundless energy. His mind buzzed with plans—ways to expand his strategies to bring peace and unity to the world.

With his usual enthusiasm, he strode toward a government building, ready for another negotiation. People greeted him with admiration, some whispering about his charisma, others about how his dreams seemed almost too idealistic to be real.

And then—

Everything changed.

In an instant, the world around him vanished.

Yuuki blinked. One moment he was on a stone-paved street, the next—he was standing in an endless void, a swirling expanse of black and crimson mist. A realm without time, without space, without logic.

His instincts screamed danger.

His body tensed. His mind, trained for battle, immediately prepared for an attack.

But then—it hit him.

A pressure unlike anything he had ever felt before.

A crushing force descended upon him, like the weight of an entire universe pressing down. His breath caught in his throat. His legs buckled, and no matter how much he fought back—he collapsed onto his knees.

A voice, smooth yet commanding, echoed through the void.

"Welcome, Yuuki."

Yuuki gritted his teeth. "Who's there?! Show yourself!"

He tried to move, but his body wouldn't obey.

He tried to activate his skills, but they failed to respond.

It was as if everything that made him special, everything that made him powerful, had been stripped away.

And then—he saw him.

A figure shrouded in a dark cloak, his face obscured, yet his presence dominated the space.

This was no ordinary person.

Yuuki's entire being screamed in warning. This was a being far beyond his comprehension.

The cloaked figure stepped forward, his very movement making the air itself tremble.

"You will be useful to me, Yuuki," the voice declared, calm yet absolute. "From now on, you will serve me."

Yuuki's eyes widened.

"What?! Like hell I will!"

The figure ignored him. "You will be my invisible hand, controlling the West and the East. The leader of my already established guild. You will move the world according to my will."

Yuuki tried to speak, tried to retort, but his lips refused to move.

Panic set in.

His body, his will, his thoughts—none of it was his own anymore.

"Let me go!" Yuuki screamed in his mind, but his voice never reached the air.

He summoned every ounce of his power, every skill, every technique he had learned—all useless.

The figure moved closer, his unseen gaze piercing through Yuuki's very soul.

Then—he lifted a single finger.

A dark, invisible force seeped into Yuuki's very being.

A spell.

A spell that he would never know existed.

A spell so deeply embedded that even if Yuuki searched for it, he would never find it.

From this moment onward, Yuuki Kagurazaka would believe he was still free.

He would believe that every decision he made was his own.

He would continue to chase his dreams, form alliances, build power—all thinking it was for his own vision.

But in reality…

Every thought, every choice, every word he spoke—would be orchestrated by Arion.

And he would never even suspect it.

The cloaked figure tilted his head, as if amused by the irony.

Then, with a snap of his fingers—

Yuuki was back.

Standing where he had been moments before, in the middle of the bustling city, as if nothing had happened.

He blinked. Had he just zoned out?

Shaking his head, he dismissed the strange feeling and continued walking, his mind filled with grand ideas and ambitions.

All while, in the City of Eternal Night, Arion sat upon his throne, a smile playing on his lips.

Yuuki Kagurazaka—his brightest pawn.

And he would never even know it.

With Yuuki Kagurazaka now at the helm of the Free Guild, things began shifting rapidly across the Western Nations and the Eastern Empire. His vision for the world remained the same—peace through control, unity through strategy. What no one realized, not even Yuuki himself, was that his every move, every thought, was subtly orchestrated by Arion.

It wasn't long before Yuuki sought to expand his influence.

To maintain his hold on both information and power, he devised the creation of a secret organization—one that operated in the shadows, unseen and untraceable. A group that could be hired for any job, but would always abide by a singular, unbreakable rule:

"Never betray your comrades or clients."

Thus, the Moderate Harlequin Alliance was born.

A mercenary, espionage, and assassination network disguised under an elaborate, almost comical aesthetic. A band of masked clowns, each hiding their own secrets, their own vendettas.

The Founding Members of the Moderate Harlequin Alliance

Kagali (formerly Kazalim) – The true leader, operating under the guise of an eccentric strategist. Once the Demon Lord Kazalim, he was killed by Leon Cromwell, only to survive by transferring his astral essence into a new homunculus body. Now, as Kagali, he hides in the shadows, plotting revenge against the one who took everything from him.

Laplace – The carefree yet deadly fighter, a master of deceit and manipulation. He acts as the cheerful yet unpredictable wildcard, but behind his grin lies a sharp mind that sees opportunities in chaos.

Clayman – The elegant and cunning schemer. With his ability to manipulate and control others, he was the perfect candidate to infiltrate the Demon Lord Council. While he acted weak, submissive, and polite in front of the other Demon Lords, his true nature was that of a calculating manipulator.

Footman – The brute force of the group, a massive, armored figure with childlike glee for destruction. Beneath his heavy clown mask, he is a sadist who enjoys toying with his enemies.

Tear – A beautiful yet utterly ruthless harlequin, known for her merciless efficiency. While she laughs and plays, her combat prowess is nothing short of monstrous. Her love for violence rivals Footman's, making them a dangerous pair.

Each member wore a mask, a symbol of their anonymity and allegiance.

Each member had their own past, their own grudges, but they were united under one cause.

Using his powers of manipulation and his ability to act like a pathetic, weak-willed noble, Clayman was able to weasel his way into the Demon Lord Council.

He played the role of a timid and obedient Demon Lord, ensuring that no one saw him as a threat. But behind the scenes, he was building his own power, turning lesser demons and nobles into his puppets, expanding his influence within the Demon Lords.

However, despite his growing power, there was one thorn in his side—

Leon Cromwell.

The very man who killed Kazalim.

And Kazalim—now Kagali—had not forgotten.

The entire Moderate Harlequin Alliance harbored a deep grudge against Leon. Kazalim, Clayman, and the rest all waited patiently, preparing for the day they would finally get their revenge.

Little did they know, Arion watched from the shadows, smiling.

He had orchestrated Yuuki's rise. He had let the Harlequin Alliance form.

And soon, they too would become nothing more than pawns in his game.

During the years, the Demon Lord Council saw the rise of two new members—Frey and Carrion.

Frey's ascension was marked by the traditions and brutal customs of her Harpy race. She had been born alongside an older twin sister, Nazim, a rare event that shook their people. Both possessed immense latent power, but where Frey was refined and disciplined, Nazim was untamed and dangerously powerful—a mutant unlike any Harpy before her.

Despite Nazim's raw strength, the elders of their race decreed that only one could be the Queen.

And so, a harsh decision was made—Nazim was banished.

Stripped of her birthright and cast into exile, she vanished from the world, her fate unknown. Frey, though conflicted, accepted her role as Queen, using her power and intellect to lead her people to greater heights. Her strength and leadership eventually earned her a place among the Demon Lords, standing alongside the most powerful beings in existence.

The other new addition to the Council was Carrion, the proud leader of the Beastmen. His path to becoming a Demon Lord was paved with battles, alliances, and sheer force of will. Through the recommendation of Kazalim and Milim, Carrion was granted his seat, solidifying the growing power of the Council.

With their ranks strengthened, the balance of power in the world shifted once more.