In the medical world, Aurex Data Systems was a name every hospital trusted. Doctors spoke about it like a support pillar of modern healthcare. Nurses used its donor lists. Administrators depended on its reports. Whenever hospitals needed reliable medical information, Aurex was always the first place they contacted.
Aurex was famous for having the most solid and updated biological records—blood donor lists, rare blood type databases, donor ID numbers, emergency contact information, and even people registered for organ donation after death. Everything was clean, organized, and constantly updated. To hospitals, Aurex felt like a life-saving system working quietly in the background.
But Aurex had another purpose.
Behind its trusted image, the company also collected deeper biological data from hospitals and public campaigns, then sold those datasets to high-level researchers. These researchers used Aurex's information to study mutation patterns, create virus simulations, and discover new diseases early—so they could develop cures before outbreaks became disasters. Because of this, Aurex became respected not only for storing information, but also for helping the medical world predict and fight future viruses.
The company operated from a four-storey building in the city's research district and was controlled by seven leaders: Ryussei, the strategic head; Hayate, who managed data collection; Tatsuya, who controlled systems and security; Zenn, the main analyst; Yusei, who handled research partnerships; Rion, who supervised internal operations; and Shiori, who managed legal and ethical approval.
Aurex Data Systems operated like any normal company, opening at 9 a.m. and closing at 6 p.m., with employees leaving once their workday ended .
Like any onther day after fter 6 p.m., Aurex Data Systems slowly went quiet.
Lights dimmed across the floors. Departments shut down one by one. Employees logged out, locked their sections, and left the building. By the time the last elevator reached the lobby, only silence remained.
That evening, as an employee from Yusei's department was preparing to leave, Yusei stopped him near the hallway.
"Can you stay for one more hour?" Yusei asked calmly. "I need help with a restricted task."
The word restricted caught the employee's attention. He hesitated briefly, then smiled.
"Yes, sir. Of course."
Soon, the building was empty. The echo of footsteps disappeared. Doors closed. The quiet felt heavier than usual.
Yusei led him toward the elevator. As they stepped inside, Yusei didn't press a normal floor. Instead, he typed a long code into the panel.
The doors closed.
The elevator began to descend.
At first, the employee stayed relaxed. Then the seconds stretched. The floor numbers kept dropping.
-5-9-14
His smile faded.
"Sir…" he said carefully. "We've gone pretty far down. Where exactly are we going?"
Yusei kept his eyes forward."There's a secure section below," he said. "Not for general staff."
The employee nodded slowly, uneasy but still trusting.
The elevator continued deeper. His ears popped slightly. The feeling in his stomach tightened. This was far below anything the building should have had.
Finally, the elevator stopped.
The doors opened.
Cold white light flooded in.
The employee stepped out—and froze.
This wasn't an office.
The hallway looked like part of a hospital. White walls. Sealed metal doors. A sharp smell of disinfectant and cold air. Machines hummed softly behind the walls.
He turned to Yusei, confused."Sir… I've never seen this place before."
"just follow me," Yusei said.
They entered another room—brighter and colder than the last. Medical equipment lined the walls. Monitors blinked quietly. At the center stood a single bed, clearly made for medical procedures.
Someone was already there.
It was none other than Shiori, one of the senior figures of the office. She stood beside the equipment, reviewing something on a tablet. When they entered, she looked up.
"You're late," she said to Yusei.
Then her eyes moved to the employee.
Her expression changed—not surprise, but interest.
"So the test results were real," she said quietly.
The employee frowned."Test… results?"
Shiori stepped closer, her voice calm and professional.
"You carry something rare," she said. "A natural antiviral factor called Viroxx. Only three percent of humans have it. It can resist almost any disease—HIV, cancer, even unknown mutations."
The employee shook his head slowly, confused."Then… why am I here?"
Yusei pointed toward the bed.
"We need a blood and tissue scan," he said. "You know we work with many organizations to develop antiviral cures. Your blood is extremely rare. A small sample could help create a cure for HIV."
Shiori smiled slightly and looked into his eyes.
"Think about it," she said. "How much they would pay if a cure for HIV came from your blood."
Something changed inside him.
Fear faded.
Hope replaced it.
Slowly, he stepped toward the bed and lay down.
The moment he did, automatic cuffs rose from the four corners of the bed and locked around his wrists and legs.
"What—!" Panic broke through his voice. "Stop! Please!"
His breathing became fast and uneven.
Shiori picked up a syringe filled with blue liquid.
Her expression changed.
The smile disappeared.
Her face became cold and sharp, like she was a completely different person.
"I really hate acting," she said quietly. "It doesn't suit me."
She glanced at Yusei, clearly annoyed.
"Can't you make them unconscious before bringing them here? I hate all this drama."
Yusei put his hands in his pockets and replied calmly,"It's not fun that way."
Shiori stepped closer to the bed, holding the syringe.
The employee struggled, but the cuffs didn't move.
"Please," he begged, his face full of fear. "Let me go. Don't do this."
Shiori leaned in.
"Don't worry," she said softly. "It won't hurt."
She injected the serum.
The monitors reacted instantly. Numbers spiked. A sharp warning beep filled the room—then fell flat.
Silence.
The employee's breathing slowed…
Then stopped.
Shiori slowly pulled off her gloves, one finger at a time. Her face was serious, almost tired.
"If this keeps going like this," she said flatly, "we won't be able to fulfill our monthly targets."
For a brief second, her expression changed.
She smiled. Soft. Cute. Almost playful.
"But…" she said lightly, "it is fun to watch them die."
The smile vanished.
She turned back, her face cold again.
"Dispose the body immediately."
Another door slid open.
Two men entered the room wearing full protective suits—thick, sealed, and white, like astronauts preparing for space. Their faces were hidden behind dark visors. Without speaking, they lifted the body and carried it into the next room. The door closed behind them with a heavy sound.
The room fell silent.
Yusei stood there calmly, hands in his pockets, as if nothing unusual had happened.
Then his phone vibrated.
Bzzzt.
He pulled it out and answered.
A voice spoke on the other end.
"He's awake. Bring both of them."
The call ended.
Yusei slipped the phone back into his pocket.
He looked at Shiori.
"Let's go," he said. "He's awake."
Shiori's eyes sharpened slightly.
"About time."
They walked out and entered the elevator. Yusei typed in another code. The doors closed, and the elevator began to descend.
Much deeper than before.
The numbers disappeared from the screen.
Only the sound of cables moving downward remained.
Shiori leaned against the wall, arms crossed.
"You know," she said, "sometimes I forget how dangerous Calistain really is."
Yusei stared forward.
"You forget?" he replied. "Almost a thousand people died during early injections ."
Shiori laughed quietly, not amused.
"Not died," she corrected. "Collapsed. Melted. Lost control. Some didn't even last ten seconds."
The elevator continued downward.
"calistsin is not something that anoyone can withstand it even the rarest antivirus in human body ."
Yusei finally spoke again.
"That's why it's the deadliest," .
Shiori nodded.
"I wonder how that boy survived after injeting . I would love to see his powers ."
The elevator stopped.
The doors opened.
They stepped into the final underground level.
The air here felt different—heavy, sealed, absolute.
A long corridor stretched ahead. On both sides were reinforced jail rooms, more than twenty of them, each door thick and windowless. At the far end stood a single security room filled with screens and silent machines. No guards were present.
They weren't needed.
This place was designed so no one could escape.
Yusei stopped in front of Room 16.
He placed his finger on the scanner.
A soft beep sounded.
The door unlocked and slide opened
The room was quiet.
Not the peaceful kind of quiet—the kind that feels sharp, like a knife resting against skin.
Kaito sat still, his back straight, his eyes cold and focused. Across from him, the girl—still handcuffed—watched him with the same tension, as if even breathing too loudly might trigger something terrible.
They had been talking just moments ago.
But then—
Click…
A faint sound.
The unmistakable sound of a lock turning.
Both of their heads snapped toward the door instantly.
The air shifted.
The door slowly opened, and two figures stepped inside.
Their footsteps were calm. Almost casual.
Kaito's eyes narrowed.
The moment he saw them clearly, his stomach twisted.
One of them…
Her.
The girl who had kidnapped him.
His fingers tensed, his whole body going into alert mode like an animal sensing danger.
The handcuffed girl also stood slightly, her posture stiff, ready to react.
No one spoke.
For a few seconds, the room felt like it could explode at any moment.
Then—
"Ahhhh~!"
A cheerful voice shattered the tension like glass.
The girl who entered—Shiori—stretched her arms lazily as if she had just walked into a friend's house. Her face lit up with exaggerated excitement, eyes sparkling with playful mischief.
She tilted her head and smiled.
"You cutie… finally woke up."
Her voice sounded warm and sweet, like she'd been waiting forever.
Kaito's eyes widened slightly.
Shiori stepped closer, completely ignoring the deadly atmosphere in the room. Her footsteps were light, almost bouncy.
"I was wondering when you'd wake up," she continued, as if she was genuinely concerned.
Then, without hesitation—
She grabbed Kaito's arm.
Before he could react, she wrapped both hands around it tightly and leaned in, pressing her cheek against his shoulder like she belonged there.
Like she was his girlfriend.
Like this was normal.
And with a soft, almost dreamy tone, she whispered:
"Let's go on a date."
For a moment, Kaito's brain froze.
Then his entire body jolted.
"—WHAT?!"
He pulled his arm back violently, stepping away as if she was a virus.
"Get off! You're too close!"
Shiori blinked innocently, still smiling.
Meanwhile, the handcuffed girl stood up fully now.
Her expression was serious—sharp and heavy, like someone who had already suffered too much to tolerate nonsense.
Her eyes locked onto Shiori.
"Enough," she said, voice cold. "Tell me what you want."
The room grew tense again.
"I know you didn't come here just to joke around."
Shiori finally loosened her grip on Kaito and slowly turned her head toward the girl, her smile fading slightly.
Her gaze became narrow.
Interested.
Almost amused.
"Oh?" Shiori murmured, tilting her head. "So you're Emika…"
Emika didn't respond. She just stared.
Shiori's lips curled into a playful grin again, but there was something wrong with it now—something sharp hiding beneath the cuteness.
Then Shiori spoke softly, almost happily:
"So you're Emika… the elder sister of Hanamika, right?"
At that name, Emika's face changed.
The air around her felt heavier.
Her jaw tightened, and her eyes darkened like a storm forming behind them.
Shiori clasped her hands together and smiled brightly, almost like a child gossiping.
"How unfortunate," she said.
Her voice was sweet.
Too sweet.
"She had to die… for a brat like you."
The room froze.
Kaito's breath caught.
For a second, Emika didn't move.
It was like her body needed time to process what she had just heard.
Then—
Her eyes widened.
Her teeth clenched.
Her face twisted with rage.
"What… did you just say?"
Her voice trembled.
Not from fear.
From fury.
"How dare you."
The words came out like a curse.
And suddenly—
Splash—!
Three sharp bullets formed in the air.
Not metal.
Not fire.
They were made of water—compressed so tightly they looked like crystal blades.
They shot forward instantly, slicing through the air with deadly speed—
Straight toward Shiori's head.
Kaito's eyes widened.
But—
They stopped.
Just a few centimeters away from Shiori's forehead.
Floating.
Hovering in place, trembling slightly like they were waiting for permission to kill.
Emika's voice dropped low.
Cold.
Terrifying.
"Take that ba—"
Before she could finish—
Shiori vanished.
Not stepped away.
Not dodged.
She simply disappeared like she was never there.
Emika's eyes widened in shock.
And in the next instant—
A sharp pressure touched her neck.
Cold.
Deadly.
A nail.
Longer than any human nail should ever be.
Two feet long.
Thin, sharp, and pointed like a spear tip.
It hovered just one centimeter away from slicing her throat open.
Emika's breath stopped.
She didn't even realize when Shiori got behind her.
Kaito's heart pounded.
His eyes flicked rapidly between them.
How… fast?
Even he couldn't track it.
Shiori's voice came from behind Emika's ear, soft and calm.
But darker.
Like a lullaby whispered by a demon.
"Don't you dare…"
Her eyes glowed with something dangerous.
"…mock me."
Emika's body stiffened.
Her hands trembled slightly, but she didn't move.
The room felt suffocating.
Kaito could feel the killing intent pouring off them like heat.
Then—
Shiori slowly lowered her hand.
Her nail shrank back to normal as if it had never grown at all.
In an instant, the dangerous presence disappeared.
And Shiori returned to her cute, cheerful self again, tilting her head and smiling like nothing happened.
As if she didn't almost murder someone.
She looked at Emika with sparkling eyes.
Then asked innocently:
"Do you like him too?"
Emika blinked.
The water bullets vanished into mist.
"…What?"
Shiori giggled, covering her mouth.
"Hehe~ I'm going on a date with him. I know you're jealous."
Emika's expression turned blank.
Confused.
Her rage loosened just a little, replaced by disbelief.
"What… are you even saying?"
Kaito stood frozen, still trying to understand what kind of insane person Shiori was.
This girl… she's not normal.
The second figure—Yunsei—had been silent the entire time.
He leaned against the wall casually, watching everything like it was some boring comedy show.
His eyes half-lidded.
No tension.
No excitement.
Just… laziness.
Finally, he spoke.
His voice was calm and uninterested.
"Enough drama."
He pushed himself off the wall and turned toward the door.
"Come on. Let's go."
He glanced back slightly.
"You two," he said, meaning Kaito and Emika. "Just follow me."
Shiori's face instantly turned annoyed.
She puffed her cheeks like a child.
"You're not fun, Yunsei."
Yunsei didn't respond.
He simply walked out.
Shiori followed right behind him, still sulking.
Kaito and Emika exchanged a brief glance.
And with careful steps, both of them followed.
The elevator doors slid open.
The sound was light, almost cheerful.
But nothing about the air that escaped from inside felt normal.
Yunsei stepped out first.
His footsteps were calm. Measured.
Behind him came Shiori, her expression relaxed, eyes half-lidded like she was walking through a hotel hallway instead of thirty floors beneath the ground.
Then Kaito.
Then Emika.
The moment the doors closed behind them, the space felt sealed—like the world above had been cut off completely.
Shiori turned toward the panel.
Instead of pressing a floor button, she typed.
A sequence.
Not rushed.
Not hesitant.
Each press was deliberate, like she was opening something that shouldn't exist.
Beep. Beep. Beep.
Kaito's gaze locked onto her fingers.
Emika's posture tightened, instinctively shifting her weight as if preparing for sudden movement.
Yunsei didn't even glance at the panel.
He simply stood there, hands loose at his sides, breathing steady.
The screen flickered.
Then changed.
-30.
And the numbers began to rise.
-29… -28… -27…
The elevator moved smoothly.
Too smoothly.
No shaking. No mechanical strain.
It felt less like a machine and more like something designed to carry secrets without leaving a trace.
Inside, Yunsei and Shiori remained calm.
They didn't speak.
They didn't exchange looks.
They didn't need to.
Their silence wasn't uncertainty.
It was familiarity.
Kaito kept his eyes forward, but his senses were wide open.
The reflection in the metal walls showed everything—small movements, slight shifts, tiny changes in breathing.
Emika was doing the same.
Both of them were silent.
Because silence was safer than revealing what they felt.
The floors climbed.
-20… -15… -11…
The deeper they went, the more the elevator felt like a corridor between worlds.
A place where time didn't matter.
Where rules didn't apply.
Finally—
-5.
The elevator stopped.
A soft click echoed through the metal frame.
Then the doors opened.
Kaito stepped out first.
Emika followed immediately.
Their eyes swept the area.
Bright lights.
Clean floors.
White walls.
And shelves—lined neatly with binders, folders, and documents arranged with corporate precision.
It looked like an office.
But it didn't feel like one.
It felt curated.
Too organized.
Too quiet.
There were no guards.
No cameras visible.
No staff.
No movement at all.
That absence didn't make Kaito relax.
It made his stomach tighten.
Because places like this didn't stay empty unless emptiness itself was part of the security.
Yunsei stepped out behind them, taking the lead as if he owned the corridor.
Shiori followed, her steps light, her posture loose.
Yunsei walked straight to a door at the end of the hallway and opened it without knocking.
The room inside was smaller than expected.
No windows.
No decoration.
Only a table.
Three chairs.
And at the far end—
a thick steel door, reinforced, bolted, heavy enough to make it clear it wasn't meant to be opened quickly.
The air inside was cold.
Not the kind of cold that comes from air-conditioning.
A different kind.
The kind that settles in your skin when something is watching.
Kaito stepped in.
Emika followed.
Yunsei entered last.
Shiori stopped at the doorway.
She glanced inside for a second, then sighed.
"I'm leaving," she said casually.
Her voice carried no tension, no concern.
"This isn't fun anymore."
Then she turned and walked away.
Just like that.
No hesitation.
No glance back.
Yunsei didn't react.
He didn't stop her.
Didn't even acknowledge her departure.
Like she had already done what she came for.
That detail hit Kaito harder than the steel door.
Because if Shiori was allowed to leave so easily…
then she was never the target.
Kaito's gaze shifted.
And that's when he saw him.
A man was already sitting at the table.
Still.
Silent.
His hands were clasped in front of his face, fingers interlocked, elbows resting neatly on the surface.
His posture was calm, but not relaxed.
It wasn't the calmness of comfort.
It was the calmness of control.
Like the room belonged to him.
Like the entire underground floor existed because he permitted it.
Emika's breathing slowed.
Her eyes sharpened.
Kaito felt his instincts flare.
Not fear.
Something deeper.
A warning.
The man didn't look aggressive.
But his presence felt dense, pressing down on the air like invisible weight.
Kaito's throat went dry.
This aura…
It's not just strong.
It's absolute.
Emika's mind raced silently.
Who is he?
The man lowered his hands.
Slowly.
Deliberately.
His face was sharp, his gaze calm, and his eyes carried a strange stillness—like he had already decided what would happen before they even entered.
His voice came out deep.
Controlled.
Coldly polite.
"Sit."
One word.
No emotion.
No invitation.
Just an order wrapped in calm.
Kaito didn't sit immediately.
Neither did Emika.
The man didn't react to their hesitation.
He only watched them, patient like time itself was on his side.
Then he spoke again.
"I assume you're wondering who I am."
His tone didn't rise.
It didn't threaten.
That was what made it worse.
He leaned back slightly in his chair, fingers folding together again.
"I won't waste your time with introductions."
A pause.
Just long enough for the silence to grow heavy.
"You've already stepped into a place you were never meant to find."
His eyes moved to Kaito first.
Then to Emika.
Precise.
Calculated.
Kaito felt his heartbeat tighten—not faster, but heavier.
The man's lips formed something close to a smile.
Not warmth.
Not friendliness.
More like a blade showing itself.
"I have an interesting story to share with both of you," he said.
Then his voice dropped, quieter now.
Almost intimate.
"And I want you to listen carefully…"
He leaned forward slightly.