The Greatest Assassin Gets Reincarnated in Tensura

Unbeknownst to him, he was not alone.

Hidden within the folds of the void, a figure observed him with keen interest. Cloaked in absolute darkness, his presence was undetectable to even the most perceptive beings. He had been watching for quite some time—silent, calculating, assessing.

The observer was Noir, one of the most enigmatic and powerful Primordials. A being of pure darkness, one who had seen the rise and fall of countless entities. And now, his gaze was fixed on this nameless demon.

"Interesting…" Noir mused internally, his golden eyes gleaming from the shadows. "He moves well. There is skill, but also something more—an instinct, a refinement that sets him apart from the usual rabble. Perhaps it is his lineage…"

Noir had long since been aware of demons who bore traces of his own Noir lineage, though most were insignificant, unable to truly tap into the depths of their potential. But this one? This one had promise.

For weeks, Noir had remained hidden, watching as the nameless demon honed his abilities, tested his newfound powers, and adapted with remarkable speed. He had witnessed him take down a High Demon, absorb his essence, and even begin considering his own evolution. And now, hearing the mention of seeking a True Dragon for a name, Noir decided it was time to make his presence known.

The moment came when the nameless demon stood atop a craggy outcrop, scanning the horizon, contemplating his next move.

Then—

A presence.

A pressure unlike anything he had felt before descended upon him like an ocean of darkness. It was not suffocating, nor violent, but it was absolute. It was the weight of something ancient. Something powerful.

His instincts screamed at him. He spun around, his body tensed, prepared for an attack. But what he saw made him pause.

From the shifting shadows of the landscape, a figure emerged—tall, elegant, draped in a jet-black suit that contrasted sharply with his flawless pale skin. His golden, piercing eyes bore into him, as if peering into the very depths of his soul. His aura was a void—limitless, unreadable, yet terrifyingly perfect in its stillness.

A Primordial.

He immediately knew who this was. There was no mistaking him.

Noir.

His body instinctively stiffened, not in fear, but in absolute caution. This was not someone he could take lightly.

Noir took a step forward, his movements eerily smooth, almost unnatural. Then, in a voice as refined as it was commanding, he spoke.

"You have been entertaining to watch."

A shiver ran down his spine. There was no malice in those words—only curiosity.

He exhaled slowly, forcing himself to remain composed. "How long have you been watching me?"

Noir smirked slightly, his gaze unwavering. "Long enough to confirm that you are… different." He took another step forward, hands still in his pockets. "Tell me, nameless one—do you understand the power you hold?"

His eyes narrowed. "I understand that I'm growing stronger."

"Indeed,"Noir acknowledged. "But strength alone is nothing without understanding. Your instincts are sharp, your movements precise. Yet you remain unshaped—raw potential without direction."

His jaw tightened. He didn't like being analyzed like this, but he couldn't deny the truth in Noir's words.

"Lara." He mentally called his partner. "What do we know about Noir?"

Lara's voice echoed in his mind. *"Primordial Demon. Ancient. Unfathomable. Current ranking unknown, but exceedingly dangerous. His power exceeds most High Demons and even some Demon Lords. His motives remain unclear."

He exhaled sharply. Noir wasn't just another opponent—he was a force of nature.

Noir tilted his head slightly. "You seek a name, do you not?"

That caught him off guard.

"He heard that conversation?"

Noir chuckled as if reading his mind. "Your ambitions are bold. To request a name from a True Dragon… Most would consider it madness. But I find it… amusing."

He held Noir's gaze. "And? Do you plan to stop me?"

Noir's smirk widened ever so slightly. "No. Quite the opposite. I am intrigued by your potential. You are of my lineage, after all. It would be a shame for you to perish before realizing your full power."

That made him pause. His lineage?

"Lara, what does he mean?"

"Analyzing… It is possible that your demonic essence shares traces of Noir's primordial lineage. This could explain your rapid adaptability and natural affinity for the darkness."*

He clenched his fists slightly. "Are you saying I'm directly related to you?"

Noir let out a small chuckle. "Not directly. But you carry the essence of the Noir lineage—a rare and powerful trait. That alone makes you… interesting."

His mind was racing. If what Noir was saying was true, then he had been unknowingly tapping into something far older, far deeper than he realized.

Noir's golden eyes gleamed. "I could offer you guidance. But only if you prove yourself worthy of my time."

His smirk returned. "And how do I do that?"

"Simple." Noir's aura flared ever so slightly, a black vortex of pure void energy crackling around him. "Show me your strength."

A challenge.

His blood surged with adrenaline. This was not just any fight—this was a test from a Primordial Demon.

A grin spread across his face.

"Lara, looks like we're about to have some fun."

"Agreed. However, caution is advised. This opponent vastly exceeds your previous encounters."

He took a step forward, meeting Noir's gaze head-on.

"Then let's see how far we've come."

As the nameless demon prepared for battle, he spoke quickly and firmly in his mind.

"Lara, analyze Noir to the maximum. I need every piece of information you can gather on him."

Lara's response came instantly, her tone sharp and focused.

"Understood. Engaging full analysis. Be advised—Noir is an Ancient Primordial, one of the oldest demons in existence. His power far surpasses conventional measurements. His primary affinities revolve around Darkness, Dark Magic, and Illusions. His presence is an abyss, consuming all light and making it nearly impossible to sense him. His combat style is unknown due to a lack of recorded battles, but his reputation suggests absolute control over deception, stealth, and psychological warfare. Expect misdirection, feints, and a reality that shifts at his command. His physical prowess is also remarkable—he is not to be underestimated."

The nameless demon clenched his fists as he listened. This was beyond anything he had faced before.

"Lara, I want you to help me use every skill I have to its fullest. No holding back. I need to fight at my absolute peak, or I won't stand a chance."

"Acknowledged. I will assist in real-time combat adjustments. Preparing adaptive combat sequence. Your best approach is constant movement, unpredictability, and rapid adaptability. Do not trust what you see—his illusions may warp reality itself. Use your senses beyond sight and focus on energy fluctuations. If possible, use absorption, but do not overextend. Stay sharp."

He took a deep breath, his body tensing with anticipation.

Noir stood a few feet away, watching him with an amused glint in his golden eyes.

"You're taking this quite seriously. Good." Noir's voice was smooth, almost casual, but the weight of his presence was suffocating. "Then let's see if your instincts match your ambition."

Then—

Darkness swallowed the world.

It wasn't just an absence of light—it was an oppressive force that seeped into the nameless demon's skin, muffling sound, dulling sensation, twisting his perception.

Alarm bells rang in his mind.

"Lara! What just happened?!"

"A field of Pure Darkness has been deployed. Your visual and auditory senses are compromised. Warning: multiple layered illusions detected. Your position may already be exposed!"*

His instincts screamed. He leapt back—

Slash!

A razor-thin cut appeared across his forearm, despite him not seeing any attack. Noir wasn't just fast—his presence was a ghost within this darkness, a predator lurking just beyond reach.

"He's hiding inside his own domain!"

"Correct. His control over Darkness and Illusions is seamless. Adjusting combat parameters—engaging Enhanced Perception Mode. Rely on energy fluctuations, not sight!"

A wave of energy surged through him as his senses adjusted. No longer relying on his eyes, he extended his awareness, feeling the distortions in the air, the shifts in mana.

There! A flicker of movement—

The nameless demon twisted to the side, narrowly dodging another unseen strike.

Noir's voice echoed through the abyss.

"You adapt quickly. But this is still my domain."

A thousand silhouettes of Noir suddenly materialized.

Each one identical, each radiating the same ominous presence. They surrounded him, eyes glowing like distant stars in the void.

"Lara!"

"Warning: Illusions detected. Identifying the real body… Unable to confirm at this time. You must disrupt the illusion!"

He smirked.

"Then I'll just destroy them all."

His energy surged as he prepared to unleash his counterattack—

And the real battle began.