What is he even trying to say now?
But before she could speak, the messy-haired boy in front of her simply let himself drop onto the icy stone floor. He sat cross-legged without caring that the ground was dusty and the cold seeped straight through his clothes. He hugged his arms tight across his chest as if shielding himself from the outside world, then slumped back against the old wooden counter like he’d run out of power. His eyes closed slowly—like he was retreating into a private world no one else could reach.
Ingrid froze where she stood, staring at him in bewilderment. Her eyes widened a fraction before she snapped, irritation bleeding into her voice.
“Hey! You! Don’t pull the whole ‘I’ve solved the case’ act and then—uh—fall asleep in the middle of it!”
Her tone was sharp, annoyed and genuinely baffled, but what she got back was absolute silence. No reply. Not even the smallest movement from the messy-haired boy.
Heat crawled up Ingrid’s face. She could feel several pairs of eyes from different corners of the library turning toward them… toward the “weirdo” pretending to sleep and the “accomplice” standing guard beside him.
Damn it… this is humiliating.
She pressed her lips into a thin line and shifted her feet, unsure what to do with herself. If she crouched down to shake him, she’d become even more of a spectacle. If she walked away, she’d look cruel—like she was abandoning a friend.
Each second dragged by, slow and torturous, as if the clock’s hands had been weighed down with iron. She tried to act casual—arms crossed, staring at the ceiling, the bookshelves, anything that wasn’t Rein—just to mask her embarrassment.
Wake up already, you idiot, she screamed internally.
Then her ears caught something.
A soft snore—steady, rhythmic.
Ingrid stiffened and stared down at him in disbelief. That snore was too consistent—too deliberate—to be real sleep. It felt like he’d deliberately slapped a giant “Do Not Disturb” sign right onto his forehead.
“Oh… wonderful,” Ingrid muttered, despairing. She wanted to rub her temples. “So now I’m seriously standing here guarding a guy who’s fake sleeping?”
In that endless awkwardness, she tried to distract herself by watching Master Rachel, who had just risen from her chair.
The elf instructor dismissed the final group of three, sending them to rest, before heading over to Tara’s group in another corner. They spoke for a while at a distance. Ingrid tried to listen, but she caught nothing beyond Tara and Sally’s responses, which sounded… normal.
While Ingrid was bent in thought, wrestling with the case’s maddening contradictions, soft footsteps approached from directly in front of her.
When she looked up, she saw Master Rachel walking straight toward her.
The elf woman’s face was as expressionless as ever—like it had been carved from marble. No emotion surfaced for anyone to grasp.
Oh no… Ingrid thought. A spike of nervousness flashed through her. She knew Master Rachel wasn’t the type to let anything slide.
In the entire Academy, who didn’t fear the cold, red-haired elf instructor?
Master Rachel stopped in front of Rein. Ingrid nearly forgot how to breathe.
She watched Rachel look down at the messy-haired boy, still “sleeping” without so much as a twitch. Ingrid almost reached out to jab Rein awake—hard—so he’d own what he’d started.
But before Ingrid could do anything, Master Rachel did something that made Ingrid go completely still.
Without hesitation, the elegant, strict elf woman lowered herself and sat cross-legged on the dusty stone floor right beside Rein. She didn’t spare her pristine white cloak a single glance.
The act was simple.
The impact on the entire room was enormous.
Ingrid blinked rapidly, her mind struggling to process the scene. She stared at Master Rachel sitting next to Rein like they were old friends—even though Ingrid knew exactly how untouchable and lofty the elf woman’s image was.
Soft murmurs rose from different clusters of students. Before long, everyone’s attention drifted toward this small circle.
Ingrid felt as if she’d been dragged into a bizarre situation with no escape. The golden-haired girl shook her head faintly, sighed—
“Of course it has to be like this…”
—and lowered herself to sit as well, keeping the most polite distance she could manage.
“Very convincing performance, Rein,” Master Rachel said. Her voice was calm, but edged with a sharpness like a blade. Her gaze stayed fixed on the empty space ahead. “But your pulse is beating twelve counts too fast for someone who’s asleep.”
Rein’s irritating snoring cut off instantly.
Slowly, he cracked one eye open and looked at the elf woman with weary caution. “Master… you really have no sense of humor,” he drawled.
Master Rachel’s lips lifted slightly. A smile—beautiful and faintly enigmatic—appeared on her face. Her crimson eyes remained cool, yet strangely enlightened.
“Living a long life as an elf creates its own problems,” she said, her tone even but undeniably serious.
Rein studied her, brow tightening briefly before easing.
Rachel released a soft breath, as if some thought still circled inside her.
“Emotion…” she began, her voice a shade quieter. “It suits people like you. It shows the value of your short, fragile lives. But for me…”
She paused. Something like hidden pain flickered in her eyes.
“It becomes a scar that never fades—lasting for centuries.”
Her words stilled the small circle for a moment.
Rein listened closely. He nodded once, his expression turning thoughtful, as if trying to understand what she meant.
“I think… I understand how you feel,” he said, genuinely serious.
Rachel raised one brow slightly at that. She looked at him for a long time, as if analyzing every syllable and every tone, then asked—her voice shifting subtly, like she was testing something:
“Then tell me,” she said softly, “what have you gained as an observer?”
Rein closed his eyes again and leaned his head back against the wooden counter with lazy ease. Light from the mana lamps overhead glinted across his dark hair.
“And what did those two extras say?” he murmured, his tone lazy—almost dismissive.
The question made Ingrid frown. She stared at Rein, puzzled thoughts spinning.
Which two “extras”? Tara and Sally?
Master Rachel didn’t answer. Instead, she tilted her head—wordlessly asking him to continue.
Rein stayed in the same posture, eyes still closed. After a beat, he spoke again, voice flat and casual.
“They’re probably insisting, very firmly, that… ‘Lucien just stopped by to greet someone he knew.’ No argument. No conflict. He simply stopped to say hello—then walked away like a gentleman… right?”
Ingrid snapped her gaze between him and Rachel. Suspicion began to form as she realized something.
Rein had been sitting here the whole time.
And the distance from here to where Tara and Sally had been talking was far too great for an ordinary human to catch their quiet conversation.
The elf woman’s mouth curved again—cool, alluring, and somehow frightening. Ingrid felt something hidden behind that smile, as if Rachel and Rein were playing a game no one else could keep up with.
“I didn’t realize,” Rachel said evenly, her crimson eyes narrowing slightly as if she were appraising Rein like a rare creature, “that your hearing was comparable to ours… to an elf’s.”
Rein opened one eye and met her gaze directly, then shrugged as if it meant nothing.
“No, it’s not like that. My ears are just normal human ears,” he replied simply—yet with unmistakable confidence.
“And…?” Rachel’s tone shifted again, now tinged with genuine curiosity.
Rein let out a soft sigh, then answered with a voice that carried a faint hint of playfulness.
“I was just guessing,” he said, a faint playfulness threading his voice. “Probably because I’ve watched too many dramas—whatever you call them here. The syrupy kind. Whenever someone dies after speaking to someone, the key witness always recites the same prefab line. It’s painfully predictable.”
Rachel stared at him, still undecided on whether to believe him. Ingrid, meanwhile, kept her brows knitted tight—her suspicion toward Rein growing by the second.
Wait—he watches dramas? With who, exactly?
“Hmph…” Rachel made a quiet sound in her throat, as if she was willing to accept the logic—yet the agreement came laced with lingering wariness. Her lips pressed together, then slowly relaxed.
“Correct. They insist Lucien only stopped by to greet them, then left—nothing out of the ordinary.”
There was something in the elf instructor’s tone that suggested she still wasn’t fully convinced.
Rein, leaning against the counter, lifted a hand and rubbed his chin out of habit before speaking again, calm and flat.
“Everyone’s holding something back. That’s why the testimonies don’t align. And as for the blackout—if it wasn’t magic, there are only a few possibilities left.”
“There were no traces of magic on any of the seven students,” Master Rachel said. “And Mind Bending wouldn’t slip past detection.”
Rein gave a small nod—acknowledging both her words and the weight showing on her face.
“Yes. That’s why it feels like someone walked in and kicked the whole evidence board over—scrambled everything—to hide something else.”
He paused, then continued, still even, but a touch more serious.
“As if they intended to make the whole thing so tangled that we can’t reach any answer at all.”
“You’re saying someone deliberately muddied the water—to conceal what lies underneath,” Master Rachel added, her voice turning cold again.
Ingrid looked between them, baffled. She shook her head slightly, tracking their exchange.
“Wait,” Ingrid cut in. “When did the two of you start coordinating? I’ve been standing right here the entire time—so why do I feel like I’m missing half the conversation?”
Her round eyes widened; her lips parted with disbelief. She looked like a kid realizing she’d missed something important.
Rein narrowed his eyes at Ingrid, thinking. Her face was openly confused, like a million questions were spinning behind her glasses. He sighed, deciding to say it out loud—despite knowing it might not help.
“I don’t think Master Rachel let me sit in because she wanted to detain me as the prime suspect,” he said evenly. “I think she wanted an outsider—someone watching from a different angle. And if everyone here still believes I’m suspect number one, then my presence serves one purpose…”
His gaze sharpened.
“…to make the real culprit lower their guard and leak tells. Correct, Master?”
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He straightened up, then turned to meet the elf instructor’s eyes. The last line carried a faint edge of challenge—as if he wanted to see how she’d respond.
Master Rachel raised an eyebrow slightly. A small smile appeared at the corner of her mouth. She nodded once, then answered in the same casual tone one might use for a mundane remark.
“Half correct. The moment you demonstrated that modified Delay Casting technique, I thought: if you were the murderer, you wouldn’t be foolish enough to jump into the water and soak yourself.”
Her smile thinned.
“But now that you’re soaked, there’s no reason not to use you.”
Her words were like a needle—piercing the wall of confidence. Rein chuckled under his breath, but his eyes held a glint that said he wasn’t surprised at all.
“Fair,” Rein said, leaning back against the counter again, relaxing. “By the book, this is the most rational division of roles.”
He turned toward Rachel, his expression easing further.
“Master is the one with rank and authority. You can walk into an interrogation room without trying. Every eye locks onto you—because you’re the most important piece on the board.”
He pointed at himself and continued, his tone now faintly sardonic.
“And me? I’m the one nobody cares about. The guy standing behind the ‘one-way mirror’—watching everything from body language to tiny tells people in the room don’t notice. If I walked in with you, they’d be on guard so hard nothing would ever slip.”
“One-way mirror?” Ingrid tilted her head, suspicious. “You mean camouflage magic?”
Rein rolled his eyes upward, smirking.
“Close enough. If you want the simple version, think of it like a cheap detective movie trope.”
“You always use weird terms like that—how is anyone supposed to understand you?” Ingrid shot back, irritation and fatigue mixing in her voice.
Master Rachel, who’d been listening quietly the whole time, asked without even turning to look.
“And now… what has a ‘man behind the mirror’ like you gained?”
Rein fell silent for a moment. The playful look from earlier disappeared, replaced by a heavier, more serious blankness. He raked a hand through his hair until it was even messier.
“Too much… too much that it makes everything messy,” he said, voice firm but worn.
“What do you mean?” Ingrid jumped in at once.
“The possibilities are… too many,” Rein murmured, more to himself than to her. “Until the event is ‘observed’ and pinned down, everything stays in superposition.”
He glanced around the room—at each cluster of students whispering among themselves.
“It’s like everyone in this room is both innocent and guilty—until we force reality to choose.”
He paused, letting that hang, then continued.
“Right now, the story can flow in every direction. And we’ll never know until we find something—some variable—that makes everything sharper, and collapses the superposition into a single outcome.”
“Superposition?” Ingrid repeated. Her lips twitched as she tried to make sense of it. “You’re saying everyone can be two things at once?”
Rein didn’t answer immediately. Instead, he looked to Master Rachel—who was thinking as well, as if his words had sparked something.
“Then it means we may be overlooking a key variable,” Master Rachel said softly, more to herself than anyone. “A variable that links everything together…”
Rein nodded.
“Yes. And what if someone is deliberately building an incoherent narrative—to divert attention away from that variable?”
His eyes locked onto Rachel. She stayed still, thinking—then suddenly spoke, her voice firm and clear.
“And in a situation like this, the least reliable variable is…”
Rein’s mouth curved into a thin smile as Master Rachel completed the thought.
“People.”
Rein narrowed his eyes slightly, his gaze fixing on the oak door to the librarian’s room. Even in the dim light, the damage was obvious—impact marks, a broken latch, clear signs of forced entry.
“Words can be twisted. They can lie. Or people can simply remember them wrong,” Rein said softly—then his tone hardened with certainty. “But actions leave traces. Cause and effect always carve their marks.”
Master Rachel closed her eyes slowly, as if giving herself a moment to absorb the idea. When she opened them again, her scarlet gaze felt sharp enough to pierce straight through him.
“You’re saying,” Rachel replied, calm yet razor-edged, “that you want to see those ‘traces’ yourself.”
Rein answered with a single, quiet nod.
“Librarian Belle already showed me the room once,” Rachel said. “I found signs of rummaging—someone searching for the Arcane Key. Nothing more. But if it helps complete your hypothesis, I’ll allow another inspection.”
As she spoke, the elf instructor rose. Her white cloak unfurled with gravity and fluttered faintly with the movement. She brushed at her sleeve with casual indifference, then turned toward the group gathered at the far corner of the great hall.
She stood to her full height, the white cloak swaying slightly, and again flicked away dust no one could see before facing the clustered students.
“Everyone,” she said, her voice carrying across the hall. “Sit by the counter. No one leaves without my permission.”
A low ripple of whispers passed through the students. A few shifted uneasily, but the moment they met Rachel’s eyes, they fell silent—no one daring to protest.
Rachel walked straight to Librarian Belle. The elderly woman stood with her arms crossed, worry written across her face. She met Rachel’s gaze for only a heartbeat before lowering her eyes, lips pressed tight, as if swallowing a surge of emotions.
Belle flinched slightly when Rachel stopped in front of her. Her voice trembled as she tried to speak.
“M-Master Rachel… I—”
“Open your office, Belle,” Rachel said—flat, absolute. “I want Rein and Ingrid to examine the inside.”
“B-but!” Belle’s eyes widened; shock was plain on her face. “That’s the crime scene! And those two are first-years—letting them inside will—”
“I’m tired,” Rachel replied—short, clipped, final. She lifted a hand to her temple lightly, like someone who’d burned through too much energy tonight.
“Tonight I’ve spent too much power to re-check every small detail twice. Those two are my temporary assistants. They will document anything I might overlook.”
She paused, then tilted her head slightly. Her sharp gaze pinned Belle, who had gone pale.
“Or are you questioning my judgment?”
Belle shook her head instantly.
“N-no! If it’s Master’s order…”
Rein and Ingrid slowly rose from the floor when Master Rachel signaled with a nod. The elf instructor lifted her hand slightly—an unspoken command for them to follow Belle inside. Ingrid flicked a glance at Rein; they exchanged a quick nod, then followed the elderly woman, who led the way with steady composure.
Master Rachel remained outside with her arms crossed. She leaned against a stone pillar, watching them go. Her scarlet eyes stared through the open doorway without revealing the slightest emotion.
Belle led them to the door of her office and paused. One hand reached for the ice-cold doorknob.
“Too damaged to lock properly anymore,” she murmured, more to herself than to them.
The thick wooden door—once a symbol of safety—was now little more than a violated barrier. With barely any force, she pushed it open. The hinges complained with a long, echoing creak, and Rein and Ingrid found themselves exchanging a brief, involuntary glance.
The moment they stepped inside, both halted as if spellbound by what lay before them.
The librarian’s office was a rectangular room—much larger than they’d expected. Its high ceiling made the space feel deep, secretive, heavy with hidden things. Structural lines blended seamlessly into the library beyond, while thick brass pipes clung to the walls and climbed toward the ceiling—part of some complex mechanism that now sat utterly still.
The room was dim—lit only by silvery moonlight through a tall Gothic window and the weak glow of a dying mana lamp. Together, those lights painted long shadows across the room, creating an atmosphere that was both unsettling and strangely captivating.
On the left and right, old-style bookcases rose all the way to the ceiling. They had once been packed with vital documents and ancient tomes—now they looked like a battlefield after a frantic search.
Books had been torn out and tossed everywhere. Some had ripped covers; others were crushed beyond recognition. A rolling ladder still leaned against the shelves, but it sat at an awkward angle, as if someone had climbed it in blind haste.
The smell hit Ingrid first: old paper, bookbinding glue, faded ink—mixed with thick dust hanging in the air until she almost sneezed. She raised a hand to cover her mouth and nose.
“This smell…” she whispered to herself, shaking her head as if to fling off the discomfort.
A faded red carpet—so worn its original fabric was barely visible—was buried under piles of books. Some lay open face-down; many pages were creased and wrinkled; others were torn as if ripped away in a rush.
Rein walked carefully, trying not to step on any of the books. His pace was slow, his eyes sweeping the room with methodical precision.
Ingrid’s gaze slid to the right and found a long worktable used for book repair—glue jars, brushes, binding needles, leather scraps. Strangely, it was the only area left untouched.
The main desk sat at the far end beneath the window: a massive oak desk belonging to Librarian Belle. Even from the doorway, they could see everything on it had been scattered.
“Looks like someone was searching for something in here,” Rein said quietly as he kept moving.
Ingrid followed, her face just as full of suspicion. Before she could speak, Belle’s footsteps sounded behind them. The elderly woman entered, her expression grim. She crouched to inspect something on the floor, then answered the question they hadn’t yet asked.
“Someone came in here,” she said firmly. “And they knew exactly what they were looking for.”
Rein stopped and turned to her immediately. “The Arcane Key to unlock the Mana Chain in the Forbidden Section—right? Where was it kept before?”
Belle let out a heavy sigh, irritation in her face. “It used to be in that desk drawer,” she said, pointing to the main desk. “But now… the culprit broke the drawer and took it.”
Rein nodded. He walked straight to the desk and bent to examine the damage closely. Ingrid stepped nearer, standing beside him, and asked in a low voice—careful not to disrupt his focus.
“What do you think? See anything?”
Rein didn’t answer right away. He kept inspecting, then finally spoke.
“Not much…” His tone was flat.
“The other drawers were yanked out and dumped—blind searching. But this one is different.”
He pointed at a brass lock plate that had been twisted out of shape, catching the moonlight.
Ingrid leaned closer, eyes tracking his finger. Her brow tightened.
“So?”
“It was locked, and the culprit didn’t have time to pick it,” Rein explained, eyes still fixed on the mark. “So they used the oldest method—brute force”
Ingrid exhaled softly, then continued in an analytical tone.
“And how can you be sure it was only force—no magic involved?”
Rein lifted his head and met her gaze. His face and voice stayed calm.
“Because if there were, Master Rachel would’ve detected it already.”
It was true. Rein wasn’t even relying on mana vision—his condition was too rough. He needed to conserve strength and mana for when it actually mattered.
If someone else could verify magic traces, why waste effort repeating the same check?
Ingrid fell quiet for a moment, thinking. Then she murmured to herself, a hint of disappointment slipping in.
“So we didn’t gain anything beyond what we already suspected…”
Suddenly, a sharp exhale through the nose sounded from the other side of the room—Librarian Belle, unable to hide her displeasure with the situation.
Rein stood up to his full height and swept his gaze around the room.
“It’s not that bad,” he said. “At least… this room is lying.”
He lifted his sharp-featured face slightly.
“This room’s a mess,” he said suddenly, almost to no one in particular.
Ingrid looked around as he spoke, adjusted her glasses, and gave a small shake of her head.
“He was in a hurry—either searching fast, or fumbling in the dark.”
Rein’s eyes drifted to the window, where the light of two moons in Arath’s sky spilled in—bright enough to make out details.
“Yeah. But this room wasn’t pitch-black. Arath has two moons—which means a few hours earlier, it was brighter than this.”
As he spoke, he rubbed his chin, studying the room. The piles of books scattered across the floor and corners made his brow crease.
“If it were you, Ingrid,” Rein asked, “and you had to find a key—where would you look first?”
She went still for a moment, thoughts racing. Then her round eyes behind the lenses lit up.
“The desk. Anything important is kept where it’s used—not hidden for no reason.”
Rein paused—then smiled faintly.
“Exactly.”
His gaze fixed on the book-repair table pressed against the wall near the front of the room. Moonlight from a small window glinted off its aged wood. It was obvious nothing there had been disturbed.
“That table hasn’t been searched at all. And that isn’t strange.”
“Because the culprit already knew the key wouldn’t be there. It would be in Librarian Belle’s desk drawer.”
The moment those words left his mouth, Belle—silent until now—snapped her head toward him. Suspicion flickered in her eyes. She didn’t like Rein—but his words hit too close to ignore.
“Are you saying the Arcane Key wasn’t the only objective?” the elderly woman asked, wary—but clearly intrigued.
Rein nodded slightly, answering calmly.
“I’m not entirely sure yet. But it’s possible. At the very least… this room is trying to hide something.”
Then he turned to Ingrid beside him, his gaze carrying quiet confidence.
“See? We have a witness that can’t lie—because it isn’t human.”
He tapped the desk once. The sound echoed too loudly in the silence.
“Right. The culprit ignored the repair table and went straight to this desk instead. He—or she—started by opening the drawers one by one. And when they couldn’t find it, they finally broke open the locked drawer.”
Rein stopped, frowning as if assembling a puzzle in his head.
“But wait…” he murmured, almost to himself. “But wait… What if our sequence is wrong?” The culprit might have broken the locked drawer first to take the key—then started tearing through the other drawers to look for something else…”
“For what?” Ingrid asked, her forehead creasing. “Why waste time doing something that complicated? If they already got the key, why dump everything out, make a mess, and even knock over piles of books like it’s a game? You said they had limited time.”
Rein’s eyes roamed the room, tracing the walls—until they stopped at the back-left corner. His expression shifted, as if something clicked.
“Excellent, Ingrid. That question is exactly the point. Who would waste time scattering books—unless they were hiding something else?”
All three moved at once toward the corner. Dozens of old books lay strewn across the floor, piled so thick there was barely any space between them.
Rein knelt beside the heap, eyes locked on a brass pipe that ran down the wall to that area.
“Look at this…”
He began lifting the books away one by one, careful not to disturb anything else, setting them neatly to the side. Ingrid, though confused at first, crouched and helped without a word. Belle stood nearby, watching every movement with intense interest.
Before long, something dark emerged beneath the books: a pitch-black brazier—large, roughly half a foot tall, with four legs—knocked over on its side. Black ash had spilled in a ring around it.
Rein froze.
“What is this?” he asked, brow tightening, suspicion plain on his face.
“An herb brazier,” Belle replied, her expression relaxing slightly as she spoke of something familiar. “The library burns focus-enhancing herbs in it every morning and afternoon.”
Rein straightened and immediately pressed on.
“And the smoke from those herbs gets sent through this brass piping into the library, right?”
Belle nodded, answering in a serious tone. She even explained the types of herbs and the exact times they were burned, in detail.
Ingrid, still kneeling, picked up a book lying near the brazier. The moment she lifted it, bits of dried leaf fell out. She gathered them into her hand and examined them—Her expression tightening with unease.
“Wait…” she murmured, staring at the fragments. “This shouldn’t be like this…”
Before anyone could ask what she meant, she reached out to turn the brazier and get a clearer look.
The instant her fingers brushed the cold metal—
The brazier flared violently with violet light.
A spinning magic circle bloomed at the mouth of the brazier—
and in the same heartbeat, a purple-black arrow shot straight at Ingrid—at point-blank range!
These entries expand the lore and mechanics introduced in this chapter.
Completely optional—read only if you enjoy diving deeper into the system.
"Observer" Role
– A metaphor Rein uses to describe his involvement: he's not the interrogator, but someone watching from the sidelines to pick up subtle tells and inconsistencies.
– Compared to standing behind a "one-way mirror" like in a detective drama—gathering insight others miss.
– Rein’s "observation" position allows him to lower the guard of suspects and analyze behavior.
– Rein compares the uncertainty of the case to the quantum concept of "superposition"—where multiple states exist until observed.
– In the context of the case, suspects are both guilty and innocent until the narrative "collapses" into truth via new variables or evidence.
– Rachel and Rein agree that people's memories and testimonies are inherently unreliable.
– Instead, “actions leave traces”—evidence that can’t lie, which they prioritize.
– Rachel authorizes Rein and Ingrid to re-investigate Librarian Belle’s office.
Discovery:
– Arcane Key drawer was clearly forced open.
– The book-repair table was untouched, suggesting the culprit already knew the key wouldn’t be there.
– This implies insider knowledge—possibly a motive beyond the key.
– A hidden herb brazier was discovered beneath a pile of scattered books in the corner of the room.
– It normally burns focus-enhancing herbs, the smoke distributed via brass piping into the library.
– Upon inspection, the brazier was found booby-trapped:
— Re:Naissance