Code:Null.Refrain — In the Client’s Shadow

The stillness before dawn visits only the deepest depths of the city’s districts.

A residential decommissioned zone beyond the central sector—a room in an old building tucked away in one corner.

Tools carelessly placed against the wall, old-fashioned monitor screens, and prosthetic units under maintenance emerged from the dim shadows. The fluorescent lights on the ceiling flickered intermittently, failing to provide steady illumination. Yet somehow, that imperfect brightness carried a sense of comfort.

Leon sat deep in a metal-framed chair in one corner of the room. He toyed with the disassembled parts of a pistol in his hands, polishing each piece one by one with a cloth soaked in machine oil. Between his work, he occasionally raised only his eyes. Beyond them sat Yui on a simple sofa, operating a faintly glowing terminal.

Silver hair brushed against his cheek with each subtle breath. —When in this room, Yui was quiet. But not because he felt at ease. He was simply placing himself in “time when nothing is happening.” Yui silently focused his gaze on a hologram projected into empty space. Layers of light panels overlapped, weaving together streams of information.

A quiet sound trembled through the air.

—New request received.

At the terminal’s low announcement, Leon’s hands stopped moving. Without responding, Yui slid his fingertips across the interface. He began checking notification logs and analyzing the structure of the received data. His information processing speed was several times that of standard terminals. Yet there was no urgency or hurry in Yui’s movements. Like a sharpened habit, he simply accumulated only the necessary operations.

“…A new request. It arrived.”

The small voice dissolved the silence that had settled in the room.

Leon turned only his gaze toward Yui, waiting without a word. He knew that if he did so, Yui would choose and voice what was necessary. He simply respected “the time until he felt like speaking.”

After a while, Yui continued with his eyes still downcast.

“…The request content is searching for a missing person. A disappeared boy.”

“Who’s the client?”

“Unknown. The sender, the route, everything’s been disguised. It seems like they’ve relayed through multiple spell addresses. When I tried to trace it, it was immediately destroyed.”

“…Suspicious.”

Leon exhaled low. Suspicious—that wasn’t a reason to ignore it. Rather, it was evidence that it connected to something larger.

Yui’s gaze fixed on a window tinged with pale blue light. In the center of the hologram, a single image floated.

The figure of a boy leaning against a ruined wall. Silver hair. Androgynous features. Age fourteen, maybe fifteen—he looked about the same age as Yui.

“This is the target. No name. Just ‘please find him.’”

Leon rose from his chair and slowly stood beside Yui. He looked down at the boy’s face in the photograph.

…Something felt strangely empty.

The boy stared straight at the camera with an expressionless face. Yet it felt like there was nothing behind his gaze.

“What is this sense of wrongness?”

“You feel it too?”

Saying this, Yui slid his fingertip to the edge of the hologram. The image enlarged. In the background, beyond the cracked concrete wall, a pattern of intricately intertwined lines and circles faintly emerged.

Geometric—no, a structure close to spell runes.

“I feel like I’ve seen this structure before.”

“Some kind of rune?”

“Probably not just decoration. There’s no point in leaving protective spells in abandoned areas, so this is…”

Yui’s voice became slightly hoarse. Noticing this, Leon slid his gaze to his profile.

“I’ll cross-reference the database.”

The terminal panels changed all at once. Countless search logs ran. It was fast enough to take Leon’s breath away.

But—

“…Nothing.”

“Registry?”

“Zero. No birth records, no entry logs, no medical data. Not a single proof of existence.”

Yui exhaled quietly. A bitter sensation settled in his chest somewhere.

“There’s really…nothing at all.”

Leon slowly placed his hand on his chin. His voice was also low.

“…It’s been magically erased. This isn’t normal. The military, or an equivalent organization moved.”

“…”

“If we’re going to quit, now’s the time.”

At those words, Yui looked at Leon once. Then returned his gaze to the hologram.

—He’d known it was dangerous. Even so, Yui didn’t refuse.

“…Since I’ve seen it.”

The words were short and sounded almost emotionless. But that was surely just embarrassment. The truth was, he was still awkward at saying “I want you to stay with me” to this person.

“I want to find this child.”

Leon smiled slightly.

“I knew it.”

Yui narrowed his eyes for just an instant, then immediately lowered his face. Countless “NOT FOUND” characters lined the terminal’s search window. A boy without even traces of existence, let alone a name. Only a single photograph proved that “he was there” in this world.

Leon relaxed his shoulders beside him. He had a premonition this would be more troublesome than usual work. But still, if Yui had decided to move forward—there was no reason to stop him.

“The log disguise is sophisticated too. Spell tracing will be quite troublesome.”

“Fine. I’m used to extra work anyway.”

“Too used to it.”

“That’s because Leon always takes dangerous requests.”

“…You’ve gotten mouthy.”

Both laughed shortly, neither starting it. This atmosphere was strangely comfortable. Though words were few, there was a sense of being able to entrust their backs to each other.

Yui operated the hologram again. The background of the photo—the cracked wall, part of the rune was re-enlarged. The geometric pattern swayed ambiguously with light interference, refusing to focus. The only thing he could be certain of was that it was “something” artificially carved.

“Memory manipulation…no, not just record alteration. This pattern is close to traces of spell interference.”

“Memorix series?”

“I don’t know. But it’s not something that would be left normally. If it’s the echo of a spell barrier, then to fundamentally overwrite the target’s existence…”

Yui cut off his words. Deep in his chest, he felt a distant memory ache slightly. The sensation of having something erased. The urgency of needing to leave something behind.

But that was still an emotion without form.

Leon glanced at Yui’s profile and returned his gaze to the monitor.

“You’re not planning to leave this alone, are you?”

“…Yeah.”

“Then it’s decided.”

Saying only that, Leon took a black jacket from the rack behind him. The heavy leather material settled on his shoulders as if it belonged there.

Yui also stood up. His slender fingertips touched the photograph once. In the hologram, the boy remained expressionless, looking this way.

“…I wonder if anyone remembers this child.”

He said this quietly, almost muttering. Leon didn’t answer. Instead, he exhaled shortly as if chewing over the meaning of those words once.

“Where are we going?”

“The old residential district. There should be structures with the same construction as the wall in the photo.”

“Sector 17?”

“Yeah. …There are no people, so there’s a high chance something remains.”

“It’s designated as abandoned. It’s outside the Security Bureau’s patrol routes.”

“I know.”

“Don’t complain if we get attacked.”

“I won’t.”

“I can’t tell if that’s a good or bad answer.”

“…”

For just an instant, Yui’s expression softened. He lowered his eyes so it wouldn’t be noticed. Even so, Leon could tell.

Leon tossed the remaining pistol parts into his bag and loaded one magazine into his holster. During the brief preparation, Yui was also deploying an initialization sequence for Memorix on his wrist terminal.

A pale blue geometric structure floated in his palm. The spell for reading memories was as natural as breathing to Yui.

“Ready?”

“Yeah.”

Leon placed his hand on the door. The electronic sound of the old auto-lock chimed briefly.

“…Leon.”

“What?”

“…Thank you.”

That voice was just a little more honest than usual. He immediately looked away as if to cover it up, but that was enough.

“Don’t worry about it. That’s my job.”

The door opened.

Cold night air enveloped them both.

Their footsteps didn’t overlap. But they descended the stairs at the same pace.

The abandoned district’s darkness was quiet, with no sign of human presence anywhere.

And yet— an unshakeable unease remained in Yui’s chest.

A boy with no name, no records, no past. Yet the fact that he had definitely “existed.”

This request wouldn’t end as mere searching. He didn’t know why. But that premonition alone was clear.

Yui gazed beyond the night. Leon stood half a step behind him.

—They hadn’t crossed the bridge yet. But it was no longer a place they could return from either.

To search for the boy who shouldn’t have existed.