[0] - Prologue

--Chatora--

Rydberg woke with a jolt, his head sinking into a pillow that felt simultaneously soft yet unnaturally cold.

A chill slithered down his spine—not the familiar coolness of his dorm room’s air conditioning, but something sharper, more invasive. His groggy mind tried to brush it off as exhaustion. After all, he’d pulled an all-nighter to finish his final report, the culmination of a semester’s worth of work.

The last thing he remembered was hitting the submit, watching the progress bar crawl to completion, and then collapsing onto his bed with a mixture of relief and bone-deep fatigue.

But as he woke up, something felt wrong.

His bed felt smaller. The mattress was thin, its fabric rough against his skin. Gone was his usual plush comforter—only a lightweight sheet lay draped over him. Even the air tasted different—crisp, almost unnaturally pure, stripped of the faint staleness that clung to his dorm room’s perpetually closed windows.

Blinking away the remnants of sleep, Rydberg forced himself upright. He rubbed his eyes, the motion familiar yet somehow off, before looking around at his surroundings.

This wasn’t his dorm room.

Where concrete walls should have been plastered with posters, and a desk should have been cluttered with textbooks, energy drink cans, and scattered notes, he instead found himself in a small, wooden room—completely devoid of anything familiar.

The walls were simple yet sturdy, constructed from polished timber that spoke of craftsmanship rather than mass production. A small window stood partially open, allowing a cool morning breeze to rustle thin paper curtains. In the corner, a neatly folded futon rested against the wall, its presence utterly alien to his Western sensibilities.

No computer. No phone. No modern appliances whatsoever. Nothing familiar to anchor him to the life he knew.

Panic surged through him, electric and immediate. He turned sharply, searching desperately for any sign of familiarity, but there was none. His chest tightened, heart pounding against his ribs as his mind raced through increasingly alarming possibilities.

Was this a dream? Had he somehow sleepwalked into someone else’s house? Was he hallucinating from sleep deprivation?

Then he saw his hands.

Small. Chubby. Childlike.

His breath caught in his throat. Scrambling to his feet, he nearly tripped over himself—his body responding differently than the one he had inhabited for twenty years—as he rushed toward the only reflective surface he could find: a small, circular mirror placed atop a wooden dresser. The moment his eyes locked onto his reflection, a cold wave of dread washed over him, freezing him in place.

A boy no older than six stared back at him. Dark, slightly messy hair framed a face that was both unfamiliar and eerily recognizable. Wide, blue deep-set eyes filled with disbelief gazed back at him from a childish face that somehow retained the ghost of his adult features. His body was tiny and fragile-looking—a stranger’s form that now belonged to him.

“What the—?” His voice cracked, high-pitched, and breathy, completely different from the deep baritone he had known for years. The sound of it sent another wave of panic through him.

His mind reeled. This wasn’t just some elaborate prank. His entire physical existence had been transformed. His height, his voice, his face—everything about him had changed in ways that defied rational explanation.

“No, no, no, no—this isn’t real.” He clutched his head with small fingers, trying desperately to force himself awake. This had to be a nightmare, a particularly vivid hallucination born from stress and overwork, and too many late nights.

But the rough feel of the wooden floor beneath his bare feet, the cool morning wind brushing against his skin, the subtle scent of cedar that permeated the room—everything felt too real, too detailed for even the most vivid dream.

And then came the moment that changed everything.

A sharp, mechanical ding echoed in his mind, as clear as a bell yet completely without source.

[Welcome.]

Rydberg froze, his body going rigid. The monotonous word “Welcome” resonated in his head, devoid of emotion or inflection.

“What? Who said that?!”

His voice cracked as he whipped his head around, scanning the room in a frenzy. His heart hammered violently against his ribs, and cold sweat beaded on his brow. The voice—it was clear as day, yet completely unnatural. It hadn’t come from the room around him. It had come from inside his head.

Then, without warning, a translucent blue screen materialized before his eyes. It said, Welcome.

His breath hitched, and his legs trembled beneath him. He staggered backward, almost falling onto the futon, but sheer disbelief rooted him in place.

“What the hell is this?” he whispered, the child’s voice making the profanity sound strangely innocent.

He blinked once—twice—but the screen didn’t disappear. It hovered in the air, unnervingly stable, the glowing blue text crisp and clear against the simple room's backdrop.

His fingers twitched. Hesitantly, he reached out, half-expecting his hand to phase through it—to prove it was merely a hallucination. But the moment his fingers brushed against the light, a subtle ripple spread across the screen—like touching the surface of a pond. The sensation wasn't quite physical, more like a resistance against his fingertips that shouldn't have been possible.

His stomach churned with a mixture of fear and impossible realization.

This wasn’t normal. This wasn’t a dream.

He had seen things like this in games, in movies, in sci-fi novels—but never in reality. A system interface. An RPG HUD. The kind of thing that existed in fantasy, not in the waking world.

His hands curled into fists, knuckles white. He forced himself to breathe, to think. Stay calm. There has to be an explanation.

Maybe this was some kind of simulation. Like in those Matrix movies he’d binge-watched during finals week. Maybe he was lying in a hospital bed somewhere, hallucinating all of this. Maybe...

But the world around him felt wrong in its rightness. The scent of aged wood, the rustle of paper sliding doors, and the particular quality of morning light filtering through the window were all too detailed and too consistent to be fabricated.

Rydberg’s breath came in ragged gasps. His body trembled as he pressed his back against the wooden wall, seeking some kind of stability.

This wasn’t a dream. This was something else entirely.

He squeezed his eyes shut, trying to remember. I was at university...

The memory hit him like a physical blow. Yes—university. He could still see the fluorescent-lit lecture hall, the endless notes he had been cramming for exams, and the late-night club with his friends. His part-time job at the campus bookstore, where he spent more time reading than restocking shelves. The smell of fresh ink on paper. The feeling of a normal, mundane life that now seemed impossibly distant.

And his parents...

His chest tightened painfully. They had always worried about him—constantly checking on his grades, his future plans, and whether he was ‘making something of himself.’

You need to focus, Rydberg. You can’t waste time on things that won’t help you in life.

He could almost hear his father’s voice, stern but caring in his own way. His mother, always called to check on him, even when he was too busy or exhausted to answer.

Then there was her.

His throat constricted as her face appeared in his mind.

Eliza had been his escape, his one moment of peace in the chaos of university life. The way she laughed at his terrible jokes, the warmth of her hand in his, the quiet moments where nothing needed to be said. They had been dating for almost a year, and he had been working up the courage to tell her something important—something that might change everything between them. But now...

He was here. Wherever “here” was.

A cold, sinking feeling washed over him. Would he ever see them again? His parents, his friends, Eliza?

His breathing grew increasingly unsteady. No, no, no—this can’t be happening.

He grabbed his arm, digging his nails into the soft skin. Pain. Real pain. His hands weren’t glitching, his body wasn’t dissolving into pixels. His senses weren’t fading like they would in a dream.

This was real.

His stomach twisted violently with the realization.

“This isn’t possible,” he whispered, voice hoarse. “This can’t be happening.”

Just then, a new information box popped up—this time, over the wooden door. It appeared so suddenly that Rydberg jumped back, his heart skipping a beat. The sensation was utterly surreal, like being in a video game or wearing some kind of advanced AR headset that revealed hidden tooltips. The box even had a small X in the corner to close it, just like a computer window.

He swallowed hard, his eyes trembling as he forced them to focus on the text hovering before him.

[Initializing the System…]
 .
 .
 .
 [System Initialization Complete]
 .
 .

[Personal Information]
 Name: Rydberg → Reiji
 Age: 6
 Clan: None → Senju
 Chatora Reserves: Nill (0/4 Chatora)
 Prowess: Below Average
 Special Abilities: [VIP]
 Race: Outworlder [Human – Earth 412]
 Current Rank: None
 Unique Abilities: Chess Grandmaster, ???, ???
 Progression to Academy Student: 0%

He stared at the information, his mind struggling to process what it all meant. Reiji? 6 years? Earth 412? Outworlder? Chatora? Senju? And Most importantly Chess GM?

None of it made sense, yet it was displayed with the clinical certainty of established fact.

Instinctively, he focused on the X in the corner and willed the box to close. It vanished instantly, leaving no trace.

Huh. His eyes flicked back to the door, and a strange sensation prickled in his mind—like a faint, haptic buzz inside his skull. The information box reappeared. He dismissed it again, this time more deliberately, testing the response.

Weird. He could control the pop-ups with his thoughts alone. Not just that—he could summon them by focusing on certain objects, dismiss them by mentally clicking the X. It was intuitive, yet utterly foreign.

[Chatora.]

The word surfaced from nowhere—strange and unfamiliar—yet something about it felt significant like it held the key to understanding his situation.

He scanned the room again with fresh eyes. Traditional wooden architecture, a futon instead of a bed, sliding paper doors instead of hinged ones—everything exuded an ancient, almost feudal aesthetic with distinctly Eastern influences.

Where am I? A hollow weight settled in his stomach. This wasn’t just a different place. The evidence before him suggested something far more impossible. This wasn’t his world. This wasn’t Earth—at least, not the Earth he knew.

Then where—?

A new system prompt blinked into existence, cutting his thoughts short.

[New Host detected. Activating Tutorial Mode…]

Before he could react, a sudden warmth spread throughout his body. It wasn’t painful, but overwhelmingly intense, like being immersed in a hot spring. His muscles tingled, and his skin buzzed as if something was awakening inside him. Images, knowledge, and sensations surged through his mind all at once—memories that weren’t his, yet they felt strangely familiar, like fragments of a life that had always belonged to him.

He saw glimpses of his existence here—a child abandoned at an orphanage with a young mother figurine lady, growing up in a village steeped in martial tradition and violence, where power was forged through bloodshed and combat. He had no parents, no lineage, and was just another nameless orphan in a world ruled by strength and clan politics.

And the village…

A symbol flashed in his mind—a spiral-like emblem wrapped around what appeared to be a stylized leaf.

It meant nothing to him consciously, yet deep down, something inside him stirred, recognizing its significance with a certainty that transcended his confusion.

His breath hitched, becoming erratic. This was bad. Worse than bad. He was in another world altogether, inhabiting the body of a child with no status in what appeared to be a dangerous, feudal society.

And then, the system chimed again.

[System Activated]

New achievement! Chatora Awakening

Before he could even process what that meant, his body convulsed. A sharp, electrifying sensation spread from his core, igniting something inside him. It was like a dormant energy that had suddenly come alive, flowing through his veins, his limbs, and his very being.

Chatora. It wasn’t much—just a tiny flicker, a spark rather than a flame—but he could feel it. A warmth radiated in his stomach, swirling ever so faintly like a miniature sun embedded within him.

And then, without warning, the blue screen vanished.

Rydberg’s mind raced. He glanced around the room, the same uneasy feeling creeping up his spine. This wasn’t a dream. This wasn’t an illusion. Something was happening, something beyond his understanding or experience.

He mentally willed the HUD to appear again. Moments later, it flickered into existence, as if it had been waiting for him to acknowledge it. The screen was crowded with information, overwhelming him at first glance. Multiple boxes appeared each one labeled with strange options he couldn’t fully comprehend yet.

[Personal Information]
[Quest System]
[Chatora]
[Attributes]
[Interface]
[Inventory]
[Map]
[Natural Affinity]
[OUTWORLDER]

The words [Natural Affinity] caught his eye with their suggestion of hidden talents. [OUTWORLDER] made his pulse quicken with apprehension. And then there was [Chatora]—the term that seemed central to whatever was happening to him. His mind hovered over the box for a moment before he willed to select it.

Immediately, the screen expanded, showing information:

[Chatora (0/4)]
 Energy in all beings.

0% Chatora [No Attribute] (0/5)
0% Chatora [No Attribute] (0/5)
0% Chatora [No Attribute] (0/5)
0% Chatora [No Attribute] (0/5)

Further information: Unavailable.

Rydberg frowned, his child’s face scrunching in concentration. What does this even mean?

There were four slots, each locked at zero, with no indication of what they represented. And Chatora—what was it exactly? Energy in all beings was vague to the point of uselessness.

Shaking his head, he closed the ‘Chatora’ section and selected Attributes.

[Attributes]

Power (Not Measured): Normal.
 Speed (Not Measured): Normal.
 Spirit (Not Measured): Normal.
 Recovery (Not Measured): Normal.

Nothing extraordinary. Everything was labelled as Not Measured, which only added to his frustration. How do I measure them? he wondered, mentally prodding at the interface.

Curious, he navigated through the rest of the HUD, but most options led to the same frustrating result:

[Not Available Yet]

He closed the interface with a thought, letting it fade from view. The sudden silence in the room felt oppressive.

Rydberg sat down on the edge of the futon, his small body seeming to sink into the thin mattress. His mind was racing, trying to make sense of everything that had happened in the span of mere minutes. He had gone from being a stressed university student to a six-year-old child in a strange world with game-like elements.

I’m in a different body. In a different world.

The realization hit him with full force now, the implications sinking in. His old life—his studies, his friends, his family, Eliza—all of it was potentially unreachable. And here he was, small and vulnerable, in a world he knew nothing about.

A soft knock at the door startled him from his thoughts.

“Reiji-kun? Are you awake?” A woman’s voice, gentle but unfamiliar, came from the other side of the thin sliding door. “Breakfast is ready. Today’s a big day, remember?”

He froze, uncertain how to respond. This person knew him—or rather, knew the child, Reiji, whose body he now inhabited. What was he supposed to say? How was he supposed to act?

“I... I’ll be right there,” he called back, wincing at the high pitch of his voice.

“Don’t take too long. The Academy entrance ceremony won’t wait for stragglers!” The woman’s footsteps retreated down what sounded like a wooden hallway.

Academy entrance ceremony?

His eyes widened. The information box had mentioned “Progression to Academy Student: 0%”. Was this indicating about the same Academy? And if so, how was he supposed to attend when the system clearly indicated he wasn’t qualified yet?

Rydberg glanced around the room, noticing a small chest in the corner for the first time. Opening it, he found simple clothing—dark blue pants, a matching shirt with a strange collar design, and sandals unlike any he’d worn before.

As he dressed, movements awkward in his unfamiliar body, his mind was already working through the possibilities. He needed information. He needed to understand this world, this system, and his place in it. And it seemed like this Academy might hold the answers.

One thing was certain—whatever had brought him here, whatever this “Chatora” was, whatever the System entailed—his life had irreversibly changed.

And he had no choice but to adapt.

I need to be careful. I need to learn. And most importantly, I need to survive.

With a deep breath, Reiji slid open the door and stepped into his new reality.