Chapter 15: Crossroads of Thought

‘At the intersection of questions and answers—decisions, guidance, and the paths we choose.’

Before setting off for Kyoto, their plan took an unexpected detour.

Instead of the train station, Arin found herself standing in front of a familiar door—Professor Ikimura’s office.

The hallway was quiet, filled with the faint hum of fluorescent lights. 

Lined with notice boards and paper announcements curling at the edges, it carried the scent of old books and coffee—the scent of every long afternoon spent chasing unfinished thoughts.

Arin hesitated in front of the nameplate. 

「 生村智 」

(‘Ikimura Satoshi’)

Her hand hovered near the doorframe.

“I’ve never come here uninvited before.” 

She murmured.

Ren stood beside her, one hand casually tucked in his pocket, the other holding the strap of his bag. 

「なんか、それじゃまるで神主さんみたいな言い方だね。」

(“You make it sound like he’s a shrine priest.”) 

He teased.

Arin gave him a look. 

“It’s called ‘respect'.”

Ren grinned faintly. 

“When you’re sick, you see a doctor. When you’re stuck, you see your professor. Simple logic.”

She folded her arms, unsure whether to roll her eyes or laugh. 

“That’s not how consultation hours work.”

He tilted his head toward the door, mischief flickering in his expression. 

「じゃあ、今は緊急相談タイムってことか。」

(“Then maybe this is emergency consultation hours.”)

Then, a teasing glint crossed his eyes.

「さあ――見てて。」

(“Now—watch me.”)

“Ren—” 

She began, but before she could finish, he lifted his hand and knocked.

Two short, confident knocks.

“Wait—what are u doing!” 

She whispered sharply, tugging at his sleeve, but he only gave her a playful glance over his shoulder.

From inside came a calm voice. 

「どうぞ、入って。」

(“Yes, come in.”)

Ren pushed the door open, leaning in with practiced ease, as if he’d done this a hundred times before. 

He stepped in with that easy, disarming smile that seemed to get him through most situations. 

Arin followed reluctantly, her steps small but steady. 

Her fingers are still clutching the edge of her laptop sleeve like a shield.

The moment they entered, the warm scent of roasted coffee and ink greeted them.

Bookshelves lined the walls—old journals, reports, even faded travel photos pinned between them. 

It was messy, but alive.

At the desk, Professor Ikimura looked up from a pile of papers, his glasses slipping slightly down the bridge of his nose.

「火根崎くん？」

(“Hinezaki-kun?”) 

He said first, then glanced toward Arin. 

「それに、アリンさんも？ 次の相談時間には、少し早いんじゃない？」

(“And Arin, also? It is rather early for the next consultation round..”)

Ren scratched the back of his neck, sheepish but smiling. 

「おじゃまします。少し…ご指導をお願いしたくて。」

(“Sorry for the intrusion. We… might need a little guidance.”)

Professor Ikimura’s brows rose slightly, curiosity softening into quiet amusement.

「ご指導、ね。」

(“Guidance, hm?”) 

He said, closing the file in front of him. 

Arin blinked, caught off guard, while Ren chuckled. 

「学問的な懺悔です、約束します。」

(“Academic confession, promise.”)

The professor gestured toward the chairs with an easy smile. 

「じゃあ、座りなさい。昼前に二人で押しかけてくるような危機、聞かせてもらおうか。」

(“Then sit. Let’s hear what sort of crisis brings two students to my door before noon.”)

Arin sat down carefully, placing her laptop on the table. 

Ren took the seat beside her, a little too casually—leaning back as if they weren’t both uninvited guests.

Professor Ikimura adjusted his glasses. 

“So, what’s troubling you?”

Arin hesitated, glancing at her notes before answering. 

“It’s about my paper… the section on population transitions and spatial boundaries. I can’t seem to connect the urban flow data with social behavior patterns. The variables don’t align.”

The professor hummed, leaning forward slightly. 

“Ah, the peripheral zone study, yes? A complex one. You’re dealing with overlapping systems—demographics, land use, psychological mapping… You’re not wrong to be stuck.”

He turned to Ren. 

“And you, Hinezaki-kun? What are you here for?”

Ren grinned faintly. 

“Moral support, maybe?.” 

He chuckled lightly, then continued.

“But I read her outline last night—she’s close. Just missing the bridge.”

Professor Ikimura’s brows arched. 

“You read her paper?”

Arin’s head turned sharply toward Ren, half surprised. 

“You did?”

Ren shrugged. 

“You left it open.”

The professor chuckled under his breath, the corners of his mouth lifting. 

“Well, that explains the confidence.” 

He chuckled softly, rubbing his chin. 

“That.. and the essay structure resemblance. I thought the phrasing looked familiar.”

Ren rubbed the back of his neck, half sheepish. 

“Guess it runs in the family.”

“You edit my document?”

Arin gave him a look halfway between disbelief and reluctant amusement. 

“You could’ve mentioned that earlier, you know?”

“I was going to.” 

He said, leaning in slightly. 

“But you looked so serious when you were working. Didn’t want to ruin your concentration.”

The professor watched the two of them—the way Arin tried to keep her composure, the way Ren’s tone softened when speaking to her. 

There was a quiet rhythm in their exchange, one that spoke of understanding without words.

He then gestured toward Arin’s screen. 

“Show me the segment.”

Arin turned her laptop, scrolling to the section in question. 

Graphs, tables, and dense text filled the screen. 

“I’ve been trying to align the data on peripheral city spaces.” 

She began, eyes on her laptop. 

“But the behavioral shifts in mid-density zones don’t match the population flow predictions. It feels… inconsistent.”

The professor skimmed through, nodding occasionally, then stopped.

“You’re analyzing the expansion pattern as a one-dimensional shift.” 

“But human mobility isn’t linear. Think of it as layers—not just physical distance, but emotional and communal distance. Why do people stay, even when cities evolve around them?”

The professor leaned back slightly, thoughtful. 

“You’re dealing with overlapping influences—historical identity, community inertia, and the emotional geography of residents. Boundaries aren’t just structural; they’re living spaces.”

His tone was patient but probing—the kind that always made Arin straighten unconsciously.

Arin nodded slowly, scribbling something in her notebook. 

Ren, sitting beside her, listened quietly, eyes flicking between them. 

“So… it’s more like, people are drawn by something that doesn’t move, even if the world around them does?”

The professor glanced at him, amused.

“That’s… quite well put, actually.”

“A poetic simplification, but not wrong.”

Arin blinked, glancing toward Ren, then back at the professor. 

“That’s actually… not a bad way to put it.” 

She admitted.

The professor leaned back, smiling slightly. 

“Perhaps you two should look at interdisciplinary models—cultural geography, behavioral studies. Or if you’re serious about expanding the framework,..”

“Hm..” 

He hummed, searching for his thoughts.

The professor returned his gaze to her. 

“You might need a comparative model. The concept of urban sentiment layers—how emotional proximity interacts with geography—might give your argument more grounding.”

Arin’s pen paused mid-air. 

A thought flickered across her eyes. 

Then, after a beat of quiet thought, she looked up.

“In that case… maybe I should consult Professor Miya. Her work on boundary sociology and emotional mapping in Kyoto’s periphery might connect with this.”

There was a small silence.

Professor Ikimura’s brows lifted just slightly—his eyes shifting, first to Arin, then toward Ren.

Ren didn’t say a word at first. 

The corner of his mouth, however, curved—just a little too knowingly.

The professor noticed. 

His expression softened into a quiet, bemused smile. 

“Professor Miya, hm?” 

He said, voice carrying a subtle weight of implication. 

“A fitting choice.”

Arin blinked, sensing something in his tone but not quite grasping it. 

“Yes, I think her studies might be helpful.”

Ren leaned back slightly, feigning casualness but failing to hide the glint in his eyes. 

“She might be.” 

He said, a note of amusement slipping through.

The professor caught the exchange—the restrained tone, the flicker of understanding—and the faintest knowing smile curved his mouth. 

“Well, that would certainly make things easier.”

Arin hesitated just for a second, her tone even.

“I just think her insights on periphery cohesion could help me define my boundary model.” 

Arin continued, her tone purely academic, though a faint pink touched her cheeks.

“Ah, yes. Professor Miya’s frameworks are rigorous.” 

Ikimura said, nodding slowly. 

“I’d be glad to hear what she thinks once you’ve discussed it with her.”

He folded his arms, smiling faintly to himself. 

“Well then. It seems you two already have the next step planned.”

Both turned to him, startled.

Professor Ikimura continued, eyes glinting with quiet amusement. 

“Kyoto, then. Visit Professor Miya. I’ll email her in advance—just don’t surprise her the way you did me.”

Ren laughed under his breath, already standing. 

“We’ll try not to.”

Arin bowed slightly, relief and gratitude flickering in her expression. 

“Thank you, Professor.”

As they left, Ikimura watched the door close behind them.

For a moment, he simply sat there, thoughtful.

Ikimura looked between them again—the quick exchange of glances, the ease of tone—and smiled to himself, leaning back in his chair.

「あぁ、」

(“Ah..”) 

He murmured quietly, 

「協働にも、いろんな形があるものだな。」

(“Collaboration takes many forms.”)