Chapter 4 – The Mandible Ritual
The city lights bled into the horizon as Kaito sprinted through the streets of Tokyo, his breath ragged, his thoughts in shambles. His insecticide-stained jacket clung to him, sticky with sweat and adrenaline. In his ears, the voice of the Swarm System echoed like a whisper behind his eardrums, threading through his mind like silk and static.
> [Mission Update: Threat eliminated.]
[System Calibration: 12%. Initialization of First Ritual pending.]
[Warning: Ritual required to prevent bodily collapse.]
"Ritual?" Kaito wheezed, ducking into a deserted alley and leaning against a dumpster. "What kind of game are you—"
> [Initializing: Mandible Ritual - Phase One.]
His entire spine locked. A jolt of heat rippled through his core. Then, without warning, the burning sensation spread. It was as though something alive was crawling beneath his skin — scratching, digging, trying to get out. He slammed his fist against the dumpster, jaw clenched tight to keep from screaming.
His phone buzzed.
He stared at the screen. A text from his boss.
"Well? Did you clean up the mess or not? The execs are coming at 8. Don't screw this up."
Kaito's lips curled into a bitter grin. He looked down at his trembling hand — the same one that just ended the life of a bug the size of a sofa, with human-like eyes and a voice that whispered his name.
He typed back:
"It's done."
But his mind was a cyclone. What was that thing? Why did it speak his name before dying? And this... system — what had it done to his body?
Suddenly, his vision shifted. The world around him turned grayscale, except for glowing red trails leading from the alley to the street. His heart skipped.
> [Swarm Sense unlocked: Tracks of nearby mutated entities detected.]
"No," he muttered, stumbling out of the alley. "No more. I'm just a damn exterminator."
But the world had already changed. The moment he killed that thing... the veil had lifted.
---
Later That Night
Kaito limped into his tiny apartment. Mold crept along the ceiling like bruises on old skin. He kicked off his boots, barely avoiding the insect traps scattered across the floor. As he collapsed onto the futon, the system's voice returned, softer this time. Almost… motherly.
> [You survived your first encounter. The world beneath the surface has acknowledged you.]
> [Your name has entered the Registry of the Swarm.]
> [You are no longer prey.]
> [Title unlocked: First Stinger.]
> [Reward: Mandible Core x1 — stored in system vault.]
He laughed — not a happy sound, but the kind of dry, broken exhale someone makes when the world's weight has caved in.
"I didn't ask for this."
The system replied with silence.
---
Elsewhere — Unknown Location
A man sat cross-legged in a subterranean temple. Around him, beetles with faces like infants crawled in a grotesque spiral. His eyes glowed — not with power, but hunger.
> "Another one awakened?" he murmured.
A servant nodded, bowing low, antennae twitching.
> "He killed a Seer-Bug. The system accepted him."
The man's lip curled.
> "So... the Mandible Ritual has begun again after all this time."
He looked up, through cracks in the cavern ceiling.
"The game resumes."
---
The Next Morning — Kaito's Apartment
Kaito woke to sunlight piercing the window. For a moment, he believed it was a dream — until the insectile tattoo on his forearm pulsed faintly. The Mandible Core embedded beneath his skin shimmered, reacting to the light.
The doorbell rang.
He opened it to see a girl in a hoodie, her eyes sharp and focused.
"You're Kaito Shinohara?" she asked.
"Who wants to know?"
She pulled out a strange ID — not police, not corporate.
> "I'm from Sector Nine. You're not the only one who sees them. We've been tracking you since last night. You killed a Seer-class bug. That's not supposed to happen."
Kaito blinked. "Wait… others like me?"
The girl nodded. "You've got two choices. Keep running... or join us."
> "And if I don't?"
> "Then the Swarm eats you."
Kaito looked back into his apartment — the traps, the poison cans, the life of an ignored exterminator.
He turned to her.
"Fine. I'm in."
She smiled faintly.
"Welcome to the second layer of Tokyo."
End of Chapter 4