Dies Irae (Part I)

[December 25th, 07:25 JST]

Tokyo Prefecture – Adachi Ward

Morning had already settled into the city, the quiet warmth of Christmas lingering in the cold December air.

Shop shutters rattled upward along the shopping street, and people moved through the sidewalks at an unhurried pace — some heading to work, some waiting for friends, others drifting without purpose. A convenience store door chimed softly as it opened. Somewhere nearby, a train passed, early commuters lingering on platforms to avoid the rush hour.

The fog was the only strange thing.

It lay low between buildings, harmless enough that people mistook it for visible breath. Someone laughed and waved a hand through it.

Then a low growl rolled through the street.

Conversation faltered mid-sentence. A child clutched her mother’s coat and asked what that sound was. Across the street, a man stopped walking.

Something dark moved inside the fog.

It wasn’t a shadow cast by buildings. The density deepened, unnaturally dark, as if night were pressing forward in broad daylight. The man wiped his glasses, breath catching as the black mist began to surge, advancing by folding inward on itself.

A line cut through the mist.

His glasses split cleanly in half.

Chaos followed.

Almost at the same moment, a red alarm flared inside the Harmonia Foundation’s Tama Facility. Loudspeakers snapped to life, the same message repeating without pause:

C.O.D.A frequencies detected. All hands to station. This is not a drill.

Personnel began to scramble toward their designated labs and command stations. Some, however, moved into deeper underground. Security doors slid open one after another as clearance codes were input.

A reinforced chamber came alive.

Crates were unsealed. Black-lined casings marked with runic words were lifted onto carts. Along the far wall stood more than a dozen device resembling resonance generators, each housing a Novium fragment that pulsed faintly within coils of exposed framework.

“Get these airborne,” someone said. “Let’s hope this buys us time.”

The helicopter cut through the winter sky at low altitude.

Inside, the air felt heavier than it should have. The absence of conversation made it more noticeable. Harnesses creaked softly as Tempesta Unit watched the city approach through the open side door. From this height, dark columns rose unevenly across the ward, spreading where streets should have been.

Reina stood near the door, one hand braced against the frame, the other curled slowly into a fist.

On the opposite bench, Emiko leaned forward, phone clutched in both hands. The screen lit, dimmed, and lit again. No signal. She tried another number. Then the same one again.

Nothing.

Takeshi’s voice cut into their earpieces.

“Adachi Ward has been breached,” he said, skipping formality. “Level 1 through 3 CODA confirmed. The horde is advancing inward. Estimated time to reach the city center: one hour. JSDF are mobilizing to evacuate civilian, but you’re ahead of them.”

Emiko swallowed. “P-P-kun... do we know how many civilians made it out?”

There was a short pause.

“The attack was too sudden,” Takeshi said. “Survival reports are still fragmented. Focus on stopping the spread. That’s the priority.”

He hesitated, then added quietly. “I’ll update you as soon as we have confirmation, Emiko-san.”

The helicopter banked as they crossed into Adachi airspace. Below them, the city finally came into focus.

Streets were locked in place, cars crushed at impossible angles, doors flung open, belongings scattered across asphalt as if dropped mid-motion. Emergency lights flashed uselessly inside thick black fog that moved with intent, flowing steadily along the roads instead of dispersing. People ran in the same direction, stumbling, falling over one another, some looking back even as they kept moving.

Misaki tightened her grip on Nana’s arm, holding her back before she could move on instinct.

Reina broke the silence, “This isn’t just Adachi. What about the other teams?”

Takeshi’s voice returned, lower this time. “It’s nationwide. Similar resonance signatures are appearing across Japan. Other Aria Corps units are already engaging in their assigned prefectures.”

Static crackled briefly.

“The frequency pattern matches the resonance generator from the Cantus Null incident—”

His voice cut off.

Mika exhaled slowly. “So it’s the same setup.”

Takeshi came back a second later. “Yes. I just received an updated report. Researchers believe these generators are sustaining and directing the hordes. Destroying them may weaken CODA activity locally. This assessment has been relayed to all Producers.”

Reina didn’t hesitate.

“Then the generator goes down,” she said.

The helicopter hovered over a high-rise at the edge of the ward. The doors slid open.

Everyone disembarked — except Reina.

She drew in a slow breath. Her eyes sharpened.

“Basilisk. Helia. Atlas. Hold the horde. Don’t let them advance another step.”

Mika, Nana, and Misaki nodded immediately.

“Dolce. Galea. Support and extract anyone trapped until JSDF arrives. Then rejoin the line.”

Reina looked at Emiko last. The phone was still in her hand.

“Seraph,” Reina said, her voice lowering. “Stay with them.”

Emiko nodded and tucked the phone into her uniform coat.

The helicopter lifted as the girls deployed below. D-Mics in already in their hands. Misaki took the lead, her voice steady as sigils ignited in sequence.

They leapt from the rooftop, gravity twisting beneath them as their descent broke cleanly, landing between the oncoming fog and the fleeing civilians.

“Don’t stop!” Emi shouted. “Keep moving!”

In the helicopter, Takeshi relayed the generator’s location to Reina.

“It’s somewhere along the forest ridge west of Adachi.”

The hill once green, now swallowed whole by dense black smoke, came into view.

“You can stop here,” Reina ordered to the pilot.

She stepped into the cold air, D-Mic already in hand. Her controlled voice rose as her body shone and the Cantus Veil unfolded around her, bright against the daylight.

Reina touched down, sigil circles forming beneath her boots as gravity bent to her.

The horde reacted at once, shifting toward her.

Reina moved forward to meet it.

Mika and Misaki moved without needing to speak.

Their voices rose together, aligned perfectly. Mika channeled her focus into the surrounding road, stone tearing free from pavement and fractured walls, lifting and folding into rough barricades that locked the oncoming horde into a fixed route. Along the wall, Misaki’s sigil circles flared, bending gravity around the corridor and forcing the CODA toward a designated path.

The horde pressed forward. Smoke piles against itself as bodies slammed into the gravity fields, scraping and clawing, only to be dragged back and redirected again and again into a single chokepoint.

 Nana was already waiting there.

She surged forward, shouting as she sang, Flame wrapped her body as she charged into the horde, heat distorting the haze around her until her outline blurred. Her fists moved in wide, brutal arcs, fire trailing behind each strike as Level 1 and Level 2 CODA burned away on contact.

Lion-like Level 3s emerged from within the mass.

Nana raised her voice and drove her fist forward. A horizontal spiral of flame, reinforced by her Cantus Veil, tore through the crowd. Multiple Level 3s were caught in it, their forms breaking apart mid-charge. Misaki followed immediately, releasing her earlier focus to pin the surrounding CODA in place, holding them long enough for the fire to finish it work.

But the horde did not thin.

Misaki noticed it first, Then Mika. Unlike previous engagements, the numbers did not drop. No matter how many fell, more pushed forward to take their place.

It felt... too familiar.

Mika clenched her jaw as she reinforced the barricade, sweat running down her temples. Misaki adjusted the gravity field in short, uneven bursts, each correction causing her song to falter. Even Nana felt it — no matter how fiercely her flames burned, the pressure never eased.

She stood in the middle of it, a sun surrounded by black.

A few blocks away, the others moved through the wreckage.

Emi spotted a man frozen in the street and raised a water barrier over his head just as a storefront collapsed. She caught it immediately. Another group of CODA moving independently, not drawn toward the main chokepoint.

She sang, sigil circles forming as needles of condensed water rained down on the stragglers. Momo followed through, wind surging to throw the man clear. Emiko pulled a child free from the wreckage of a van and sang softly, her Cantus stabilizing wounds just long enough for them to run.

“Shelter,” Emi shouted. “Don’t stop.”

The girls moved faster.

They dragged an elderly couple from a collapsed doorway. Pulled a teenager from beneath shattered glass. Then froze as a new mass of fog thickened ahead of them, CODA shapes forming directly in their path.

They couldn’t leave. And they couldn’t stay.

Footsteps approached from behind.

“Go.” A voice ordered. “Leave the civilians to us.”

Back at the line, Nana staggered as something struck her side. She rolled, came up swinging, and barely caught the leopard-shaped Level 3 as Misaki slammed it into the ground. Nana finished it with a burning punch.

“We can’t hold this!” Nana shouted.

Misaki didn’t answer. None of them needed to. They were reaching their limit, all three listening for the same thing.

Reinforcements.

And on the forested hill beyond the city. Reina’s fight was no easier.

Lightning flared as her blade carved through the fog. The chainsaw mechanisms along her legs screamed as she moved, cutting and tearing through anything that came too close. Level 1 and Level 2 CODA burned away on contact, bodies dissipating before they could land a blow.

A pressure lingered around her.

She felt it — the same resonance as the cult raid, only heavier. The generator had to be nearby.

Multiple packs of Level 3 CODA emerged from the smoke, forming a loose perimeter. Predators with massive frames. Three elephant-like shapes anchoring the line.

But she didn’t slow.

Reina cut through the lesser CODA and drove straight into them. Claws raked past her. Teeth snapped inches from her limbs. She twisted, countered, slashed — never stopping — until her breath shortened.

Every step began to cost more.

Electricity crawled along her limbs as she sang harder into her D-Mic, forcing her Cantus to shift. The blade in her hand curved, reshaping for control over reach.

Level 1s and 2s smoked instantly when they touched her haze.

The Level 3s pressed in.

Reina dug in, pushing forward through the resistance, until she felt something different.

Back in the city, moments earlier—

The girls looked up as transport aircraft roared overhead. Two crates dropped in rapid succession, slamming into the streets near their positions. The impact split the casings apart, metal tearing open to reveal generator-like devices embedded with Novium fragments.

Without warning, the fragments pulsed.

A low resonance spread outward from the coil, heavy and unfamiliar. The CODA reacted to it. Their advance slowed, movements faltering. Some turned away entirely, drifting back into the fog as if pushed by an unseen current.

Earpieces crackled.

“Thank God,” Takeshi breathed. “They made it in time.”

“P-kun,” Misaki said, staring at the device, disbelief cutting through her voice. “What are these?”

“I’ll explain later,” Takeshi replied. “Listen carefully. New orders. Eliminate any CODA that remain affected. Do not pursue those retreating. Priority shifts to civilian rescue. These machines won’t hold for long.”

“Understood,” they answered together.

With the dispersion field active, the girls moved quickly. Slowed CODA were cleared with efficiency, then abandoned as the teams regrouped to assist JSDF pulling survivors from the streets.

On the hill, Reina heard every word.

She exhaled, a sharp, bitter smile cutting across her face.

The resistance ahead of her wavered. Disrupted Level 3s staggered as she advanced, cutting them down in swift, precise strikes. Then she leapt, electricity surging beneath her feet as she cleared the final stretch.

The device came into view. Still guarded.

Reina refocused, lifting her voice as she drove her song upward. A massive sigil circle bloomed in the sky above the ridge.

Lightning fell.

It struck cleanly around the generator’s position, thunder cracking across the hill in rapid, echoing burst.

The resonance broke, and its effects were shown immediately.

The horde’s forward momentum collapsed, movements faltering as if a command had been cut mid-execution. CODA slowly drifting back into the thinning fog and scattered, their call to invade gone, now left to wander in the wild.

Reina called for a ride back to the ward.

The streets were quieter now, broken only by the shouts of JSDF rescue teams moving through the wreckage. The rest of the Team 02 supported them where they could.

Emiko broke from the group.

She ran. The others saw and followed. Her phone was already in her hand as she reconfirmed the address that had been sent to her days ago. When she reached what remained of a hotel, she stopped and called again, hands shaking.

This time, the call answered back.

A ringtone echoed from beneath a collapsed wall.

Emiko dropped to her knees as she saw it — her mother’s phone, cracked and still ringing beside the rubble.

The sound that left her tore through the silence.