The Otaku's Odyssey: Reincarnated with a Grand System

"So... which one of you idiots wants to come at me first?"

Astrid's voice cut through the heavy silence like a blade. He cracked his neck lazily, rolling his shoulders as if preparing for a morning jog instead of a bloodbath.

His blade glinted under the flickering mall lights, stained with crimson. His long blue ponytail swung behind him as he bounced on his heels, stretching like he was getting ready to spar at a playground.

The remaining cultists didn't move. Not yet.

The mercenary leader narrowed his eyes. 'Who the hell is this brat? I didn't even see his last movement…'

The hostages were dead silent. Some trembled, others stared with wide, shell-shocked eyes. A child—no, a monster—had just decapitated one of the cultists right in front of them… and now he was smiling?

"You guys deaf or something?" Astrid raised an eyebrow. "Or do I have to start naming volunteers?"

His voice was light, almost cheerful. That made it worse.

"What the hell are you all doing?!" the mercenary leader suddenly roared, snapping out of his daze. "Attack the damn kid! MOVE!"

One of the remaining swordsmen gritted his teeth and stepped forward with a roar, blade raised high. He didn't wait for backup.

Behind him, the two mages began muttering under their breath. Their eyes flashed as magic glyphs formed in the air—pale blue and violet, swirling with crackling mana.

Astrid's smirk faded.

"Tch. So that's how it is, huh?" he muttered, sliding one foot back. "All of you at once."

His eyes sharpened like drawn blades.

"Alright then… let's make this painful."

The swordsman lunged first, blade swinging wide—reckless, furious. Astrid ducked under it smoothly, like he'd done it a thousand times before.

"Nice try," he said casually, sidestepping.

The cultist cursed, spinning around to attack again.

Astrid leaned away, just far enough for the blade to whistle past his face.

"That was cute," he added, mockingly. "Now my turn."

A flash.

Astrid's foot connected with the man's gut mid-swing. The swordsman doubled over with a strangled grunt, spitting blood as he stumbled back.

One of the mages fired a searing bolt of flame. Astrid spun sideways, dragging the dazed swordsman into the blast's path.

"GRAHHHH!"

The man screamed as fire engulfed him.

Astrid didn't flinch. "Y'know, friendly fire's a serious problem in dysfunctional cults."

The second mage finished her chant—ice shards rained toward him in a wide arc.

Astrid dashed forward, straight into the storm.

The ice broke against his movement like he was cutting through paper.

"I thought I said," Astrid appeared in front of her, sword raised—

"Let's make this painful."

---

Meanwhile…

One Floor Below.

Smoke coiled lazily through the air, dancing along the cracked ceiling tiles.

"Fireworks, huh?" the woman in the sleek black tactical suit tilted her head, watching flames lick up the stairwell. The light glinted off her visor. "Looks like those vein bastards are really putting on quite the performance."

She struck a match against her sleeve with one flick—fsssshhk. The flame flared, catching on the stick between her fingers. She slid it between her lips like it was a cigar.

"Captain," a voice crackled through her comms, "All floors below have been cleared. Squad's waiting on your word."

She exhaled slowly. The scent of smoke curled around her lips.

"Good," she said. "The party's started. Let's not miss our cue."

Then she grinned—a sharp, dangerous grin.

"What are we waiting for, then? Let's go give those cultist bastards a reason to regret waking up today."

The operatives behind her shifted like a single organism. All clad in black, their weapons gleamed under the flickering emergency lights. No names. No hesitation.

"Team A, breach the west wing. Team B, follow me. Target is on the upper level."

"Yes, ma'am!"

With a sudden surge, they moved—silent shadows racing up the stairwells and escalators, boots slamming against the blood-slicked floor.

They weren't coming to negotiate.

They were coming to end it.

---

Back to the carnage…

A flash of steel. A burst of wind. Chaos in every breath.

Astrid deflected the swordsman's furious strike with a sharp clang. Sparks flew as he twisted his wrist and dipped just as a razor-thin wind spell screamed past his cheek, detonating into the rubble behind him.

'That Aether… someone's moving fast. Strong. Closing in.' Astrid didn't glance down the stairwell. No time. His focus locked forward.

"You really think you'll last long enough for help to show up?" the cult leader snarled. His blade whipped out with unnatural force.

A gust of wind—shaped like a crescent blade—tore through the air toward the remaining hostages.

SHRRIP!

Three bodies fell before they could scream.

Blood sprayed across the wall. The screaming started anyway.

Astrid froze. His pupils narrowed. His hand clenched the hilt tighter.

A silence swept through him. Cold. Heavy.

And then—

Aether erupted.

A crushing pressure exploded outward from Astrid like a tidal wave of raw intent. The very floor beneath him cracked. The air rippled. Cultists staggered backward, instincts screaming that death had taken a new form.

Then—

BLINK.

He vanished.

The first mage blinked—then choked as Astrid's fist crashed into the side of his skull.

CRACK!

The man was airborne—launched like a missile—before he smashed through a row of seats and slumped lifelessly in the corner.

Astrid didn't watch him fall.

'I have to end this—before that damn orb awakens.'

The second mage shrieked. Her hands glowed violently with chaotic mana. "D-Die, you f**king freak!!"

She didn't finish.

Astrid reappeared right in front of her.

His blade flicked once.

SLLICK.

Her arms dropped to the ground. Blood gushed as she screamed, collapsing to her knees. Tears mixed with sweat and agony as she looked up at him—at the emotionless blue eyes staring her down.

"You… monster!" she sobbed.

SWISH.

Her head rolled seconds later.

Silence again. Cold. Absolute.

Only the humming orb pulsed now—hungrier than before.

The final swordsman let out a hoarse battle cry and charged, his strikes wide, sloppy—driven by grief and rage.

Astrid met every swing. Sparks flew with each clash. His arms moved with mechanical precision, deflecting with effortless control.

"You know what pisses me off the most?" Astrid muttered, parrying again.

He ducked under a horizontal slash, then smashed his fist into the swordsman's stomach.

Blood spewed from the man's lips.

"You kill strangers without a second thought… but lose your fucking minds when it's your turn to grieve?"

Astrid spun, swept the man's legs, and kicked him square in the chest.

The cultist crashed to his knees, breath hitching.

Astrid stood above him.

"Fuck you."

SWISH.

Another head hit the floor.

A slow clap echoed through the room.

"HAHAHAHA! Magnificent!" the cult leader stepped into view, blood dripping from his hand. The orb in his grip glowed a dark crimson, pulsing like a heart. Behind him, dozens of corpses—hostages—lay lifeless. Drained.

Astrid's eyes narrowed.

'No… it's too late. He fed the orb everything it needed.'

"You're something else, kid," the cult leader said, licking blood from his fingers. "Too strong for me to beat as I am."

He raised the orb to his lips.

Astrid's jaw tightened. "Don't—!"

But he already had.

GULP.

The orb disappeared into his mouth. His eyes bulged. His body arched.

Black veins spread beneath his skin. His muscles expanded. Bones cracked and reformed. His mouth stretched inhumanly wide as blood leaked from his eyes, nose, and ears.

Then his eyes snapped open.

Burning crimson.

A voice—not one, but many—echoed from his throat.

"Now… let me show you the true strength… of the Scarlet Vein."

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