Chapter 1: The Weakest Hunter
Rain fell hard on Tokyo, slicing through the night in sheets of silver. Neon lights from convenience stores and arcades blurred in the water-slick streets, reflecting off the puddles like fractured stars. Kairo Tanaka stood in the alley behind the Tenjin Mall, his head tilted to the sky, letting the rain wash over his face like a baptism. He was trying to forget the laughter.
"F-rank filth."
The words clung to his memory, spoken just an hour earlier by Yuji Ren, a cocky C-rank who wore arrogance like armor. They had just finished a raid on a D-rank dungeon—one of the safer kinds—and Kairo had done his job: pulled aggro on the weaker mobs, kept the team updated on mob positions, and dragged out injured members. No glory, no loot. Just scraps. As always.
He tugged his cracked Hunter Association badge from his pocket and turned it over. The chipped corner made it easy to spin between his fingers. The silver border, once a point of pride, was dulled now, worn by years of low-tier hunts and humiliation. His rank hadn't changed in three years. While others ascended, unlocking skills and power with every successful clear, Kairo stayed stagnant.
And he didn't know why.
Most Awakened could at least make it to D-rank with effort. But not him. No active skills. No stat gains. Just a weak healing ability barely strong enough to close papercuts.
But what choice did he have? Hunting was the only job that paid enough to keep his sister, Aiko, in her private care center. She'd been comatose since the dungeon break five years ago. Since the day Kairo awakened.
He wiped his face and turned toward the subway, his body aching from the earlier raid. The Tokyo Underground Guild Association building stood just a few blocks away, and he had to turn in his dungeon report before midnight. Another 8,000 yen in the bank. Enough for food, rent, and part of Aiko's treatment.
As he walked, his Hunter Watch vibrated. A red alert.
"Unregistered Dungeon Signature Detected - Location: Tenjin Mall Basement. Potential Breach Risk: Moderate to Severe."
Kairo blinked.
Tenjin Mall? He stopped mid-step. That was where he'd just been.
The alert continued: "Nearest registered Hunter: Kairo Tanaka (F-Rank). Please investigate. Backup en route."
He stared at the notification.
"You've got to be kidding me..."
The mall was closed, of course. Its metal shutters sealed and the lights dimmed. But Kairo knew a way in. Maintenance door, west side, half-hidden by a vending machine. A remnant from his early scavenger days.
He slipped in, his footsteps echoing off the concrete halls. The scent of mold and old fast food hit him like a punch. But under that was something else.
A metallic tang.
Blood.
The basement was darker than he remembered, and colder. Much colder. Frost clung to the walls, spreading in jagged veins like spiderwebs. He took a step, and his boot crunched on shattered tile.
A few meters ahead, a faint glow pulsed in the darkness—a swirling black vortex, suspended above the ground. Not a gate. Not like any gate he'd seen before.
"This is wrong," he whispered.
Suddenly, the system chimed in his ear.
"You have discovered an Unclassified Dungeon. Difficulty Level: ???. Escape Disabled. Initiating Forced Entry."
"Wait, what?!"
Before he could run, the vortex expanded, tendrils of shadow coiling around him like snakes. They yanked him forward, and the world went black.
When he opened his eyes, he was in a cavern lit by bioluminescent crystals. The air was heavy, oppressive. And silent. No system ping. No map. No interface.
He stood slowly, every muscle tight. "Hello?"
No answer. But there was movement.
Something slithered along the far wall. It looked like a centipede but was the size of a motorcycle, its carapace obsidian black with crimson highlights. Eyes like molten gold locked onto him.
[Unseen Horror - Lv. 45]
Kairo paled. That was way beyond him. A C-rank hunter might have a chance. Maybe. But not him.
The creature charged.
He dove sideways, landing hard. Pain flared in his ribs. He scrambled back as the centipede's maw snapped shut inches from his leg. He needed a plan. Anything.
His healing ability wouldn't help. He had no weapons. No skills.
But then he saw it.
A corpse. Another Hunter. Gear half-melted, but the sword still intact. He sprinted, rolled, and grabbed the blade.
The system flickered to life.
"Echo Protocol Detected. Initializing..."
The world froze for half a second. Then:
"New Ability Acquired: Echo Slash - [Absorb last used enemy technique upon kill]."
His eyes widened. "What the hell...?"
The centipede lunged. He ducked and swung wildly. The blade connected with a sickening crunch. The beast shrieked, twisting in agony. Another strike. And another.
Finally, it collapsed.
Silence returned.
Then the voice spoke again:
"Echo Absorbed: Razor Carapace (Passive Skill) - Physical defense +40%."
His breath caught. He could feel it—his skin was tougher, the pain lessened. Something deep in his body shifted, adapted.
He grinned.
For the first time in years, he felt something ignite in his chest.
Hope.
Then came the next ping:
"Warning: Multiple Hostiles Approaching."
Kairo tightened his grip on the sword, eyes narrowing as growls echoed through the cavern.
"Come on, then. Let's see what I can become."
[End of Chapter 1]