The Greatest Assassin Gets Reincarnated in Tensura

Back in the Underworld, where the skies bled black and rivers of molten darkness slithered through the broken, infernal landscape, a single figure moved with an elegance unfitting for such a wretched realm.

Diablo strode through the air, his every step measured, his form draped in a pristine, obsidian butler's suit—a stark contrast to the chaos surrounding him. His polished shoes never touched the jagged ground, and yet, the very earth seemed to tremble beneath his presence. He adjusted his white gloves with a glacial grace, his golden eyes glinting with amusement as he neared his destination.

The air crackled with raw nuclear devastation.

Explosions of radioactive fire erupted in every direction, erasing anything unfortunate enough to exist within range. Demonic figures disintegrated, their agonized screams lost within the relentless storm of annihilation. And at the center of it all…

A woman, wrapped in golden-black energy, laughed like a maniac.

Jaune—the Primordial of Nuclear Devastation—hovered midair, twirling between her own explosions, eyes blazing with euphoric madness. Her blonde hair whipped violently in the aftermath of her destruction as she hurled another sun-sized mass of radioactive energy toward a group of unfortunate demons.

"Hahahaha! COME GET SOME, YOU WORTHLESS INSECTS!" she screeched, her grin stretched wide.

Diablo exhaled softly, shaking his head as he tugged at his sleeve, ensuring his attire remained immaculate. "Still the reckless child, I see…" he murmured to himself, before allowing the barest sliver of his aura to seep into the world.

The atmosphere collapsed.

A crushing silence followed. The very fabric of the Underworld bent beneath Diablo's mere presence. The once-raging nuclear fire snuffed out in an instant, swallowed by an unseen force beyond comprehension.

Jaune froze midair, the exhilaration in her eyes flickering—replaced with confusion.

Slowly, she turned, locking eyes with the devil in the butler's suit.

"Ohhh?" she cooed, tilting her head. Her smile twitched.

Diablo descended ever so gracefully, hands clasped behind his back, his expression calm yet immeasurably condescending.

"Jaune," he greeted, voice like silk wrapped around a blade. "You call this destruction?" He gestured toward the smoldering battlefield. "How… quaint."

Jaune's eye twitched. "Quaint?!" she spat. "Do you even SEE the absolute devastation I've been dishing out?! I turned those demons into dust!"

Diablo let out a low, amused chuckle. "Dust… is insignificant. True destruction leaves not even the concept of its victims behind."

Jaune's grin widened into something unhinged, a vein throbbing on her forehead. "Alright, you smug bastard—how about I show you firsthand what my 'insignificant' magic can really do?!"

She thrust both hands forward, a colossal sphere of nuclear devastation forming between her palms. The sheer heat warped reality itself. The sphere expanded, growing larger than mountains, its core thrumming with impossible energy. The Underworld itself seemed to recoil from its presence.

With a savage grin, she launched it straight at Diablo.

The world screamed as the apocalyptic force rushed toward him—

—And then, with a single, casual flick of his gloved wrist…

It was gone.

The attack did not detonate. It did not explode. It did not even vanish. It was simply… devoured, erased from existence itself.

Jaune's breath hitched. "What…?"

Diablo was already before her, his golden eyes now piercing into her soul, his aura pressing against her very being like the weight of a collapsing universe.

"You lack elegance," he whispered.

Jaune staggered back, her instincts screaming in terror, her body betraying her bravado. She had never felt something like this before. This wasn't power—it was authority.

Diablo leaned in, his golden eyes gleaming with something dark—something absolute. His voice, silken yet heavy with menace, slithered into Jaune's ears like the whispers of a devil at confession.

"Join me, Jaune," he said, his tone betraying no uncertainty. "Serve my master, my lord—Arion."

Jaune blinked, then scoffed, tossing her head back with a wild, mocking laugh.

"Who the hell is Arion?" she sneered, crossing her arms. "Some new idiot you decided to worship? Hah! Noir, you've always been the weird one. I'm not about to start following you now."

For the first time in their exchange, Diablo's eye twitched.

He straightened his gloves, exhaling slowly as if to contain something far more sinister than mere irritation. When he spoke again, his voice was measured, but beneath its elegance lay the razor-sharp promise of doom.

"First off," he said, each syllable laced with authority, "my name is Diablo—bestowed upon me by my lord Arion." His expression darkened. "Second…"

The very air around them cracked. The Underworld itself shuddered under the sheer weight of his presence.

"You will not have a choice in the matter," Diablo continued, his voice now carrying an unmistakable finality. "By will or by force, you will follow me."

He leaned in once more, his smirk widening into something truly malevolent.

"And truthfully…" He let out a low, delighted chuckle. "I hope you refuse."

The space around them grew black, reality itself seemingly warping in submission to his power. Diablo's golden eyes burned like twin suns in the abyss.

"I would love nothing more than to show you… true despair."

Jaune hesitated for a brief moment, a flicker of something almost resembling doubt crossing her face. Then, with a cocked eyebrow and an amused smirk, she scoffed.

"You're named?" she said, incredulous. "Who the hell is stupid enough to name a Primordial?"

Diablo exhaled sharply, his patience running thin. His gloved hand twitched, but he restrained himself, barely. His voice, however, carried an unmistakable edge.

"So," he said, tilting his head ever so slightly, his golden eyes narrowing. "What will it be, Jaune?"

Jaune bit the inside of her cheek, her manic energy dimming just a fraction. She wasn't stupid. Diablo was always strong, but now that he was named? That meant one thing—he had surpassed the limitations of a Primordial.

There was no way she could win.

With a reluctant sigh, she folded her arms. "Fine. But if this so-called 'lord' of yours turns out to be weak, I will not serve him."

A dangerous silence followed.

Then Diablo smirked.

A slow, sinister grin stretched across his lips, his amusement genuine, yet brimming with something far darker. He took a step forward, towering over her as shadows coiled at his feet.

"Good answer…" he murmured, his voice laced with satisfaction.

The air around them trembled, and for the first time, Jaune wondered if she had just made a deal with something far worse than the Devil himself.

The Primordial Violet was an enigma wrapped in silk, a paradox hidden behind a doll-like smile. To the untrained eye, she was carefree, a whimsical beauty draped in regal attire, her every movement exuding the grace of a spoiled princess. She spoke in honeyed tones, with laughter that danced through the air like the chime of delicate bells.

But beneath that gilded façade lurked something far more sinister.

Violet was calculating, her mind a labyrinth of schemes, each move meticulously crafted like an intricate tapestry of deception and cruelty. She never acted on impulse—no, everything she did was for a reason, a step toward some greater unseen goal. While others saw the Primordials as mere beings of destruction, she viewed existence as a game, and every soul around her was a mere piece on her ever-expanding board.

And what fun it was to watch them squirm.

Violet did not simply kill her enemies—oh, no, that would be far too dull. Instead, she preferred to keep them, capturing their souls, sealing them away in beautiful jeweled trinkets or shadowy cages where they would remain at her mercy. She would whisper to them, torment them with illusions of false hope, dragging them to the brink of madness before pulling them back—only to start all over again.

Their pain, their suffering, their struggle—it was a melody she adored, an orchestra of agony conducted by her delicate fingers.

Yet, despite her sadistic pleasures, Violet was not without her own twisted sense of fairness. If, by some stroke of fate, one of her playthings found the strength to resist, to rise from their despair and break free of their torment, she would not be angry—no, she would be thrilled.

Nothing fascinated her more than those who overcame the impossible. Their resilience was intoxicating, and in rare moments of amusement, she would even reward them—granting them boons, sparing their lives, or even lending a hand in their endeavors. Not out of kindness, of course—she simply found them too entertaining to discard.

But woe to those who tested her patience.

Violet had no tolerance for insubordination.

Those who worked under her were mere extensions of her will—nothing more, nothing less. She despised interference, hated when her carefully woven chaos was disrupted by fools who thought they knew better. A single act of defiance was enough for her to cut ties—and in some cases, that meant severing something far more permanent.

She had no love for admirers, no patience for worshippers. Devotion meant nothing to her unless it served a purpose. To love the Primordial Violet was to love a storm, one that would pull you in with its beauty only to leave you in ruins once it passed.

She was the predator, and the world was her playground.

And oh, how she loved to play.