The Rooftop

On Wednesday afternoon, Kanzaki Toru finally found a window of time to be alone.

After school, Sudo dragged Yoshida off to the gym, Horikita stayed in the classroom to organize a study session for some of the higher-performing students, and Kushida was surrounded by a group of girls heading to Keyaki Mall for a shopping trip. Sakura Airi had taken her camera to the playground—she had recently been working on a photo series themed "The Sky Beneath the High Wall," and she would scout for shots in different locations every day after class.

Kanzaki walked toward the stairwell alone. He had noted the location of the door Sakura had paused to look at near the corner of the stairs yesterday. The stairwell was at the far end of the east side of the school building, a place rarely frequented by anyone.

He reached the door. It was left slightly ajar, the lock having been pried open, leaving behind a few fresh metallic scratches. He pushed the door open to reveal a narrow staircase leading to the roof. Dust motes drifted slowly in the rays of the setting sun, and the air carried a faint scent of rust.

The door to the rooftop was also ajar. He pushed it open, and the April breeze rushed to meet him.

The view from the rooftop was even better than he had imagined. The entire campus was laid out before him—to the south, the complex of school buildings and the glass dome of Keyaki Mall; to the north, the playground and the gymnasium; and further off, that grey-white high wall, its dense barbed wire reflecting cold light under the sunset. A few discarded desks and a rusted folding chair were scattered across the roof.

Kanzaki walked to the edge of the roof, rested his hands on the railing, and looked down at the campus. This was an excellent observation point. Not for observing the scenery, but for observing people. From the students playing soccer on the field to the crowds coming and going at the mall entrance, from the students entering and leaving the library to the girls chatting beneath the dormitory—the rooftop's perspective covered almost half of the campus's daily flow.

He noticed Sakura Airi crouching under a cherry blossom tree by the edge of the playground, tilting her head back to snap a photo of the canopy. From this angle, her figure looked exceptionally small and thin.

There were traces of others having been on the roof. Beside the folding chair lay a cigarette butt—not a fresh one, as the ash had already been scattered by the wind, but the filter still retained a faint smell of tar. A few scribbled, illegible characters were carved into the armrest of the folding chair.

He returned to the stairwell to carefully examine the pried-open door. The scratches on the lock were new; it must have been forced within the last few days. The technique was mediocre, not professional. The secret of the rooftop was not a single secret, but the secrets of many. It was clear that more than one person had been using this place. The owner of the cigarette butt could be an upperclassman, or perhaps someone from Class D who smoked in secret—Sudo and Yoshida didn't smoke, but he wasn't so sure about Ishizaki, that yellow-haired boy. What interested him more, however, was the folding chair. It faced the best vantage point on the roof, and there was no dust on the seat, indicating someone had sat there recently. And that position—facing the playground, slightly to the west—happened to overlook the row of benches by the field.

The very place where Sakura Airi spent her time every day after school.

He didn't linger on the roof for long. After heading back down, he left the door slightly ajar just as he had found it and went to the library. It was quiet inside, with a few students scattered in the corners reading. Hirata Yosuke sat by the window, a book spread open before him, turning pages with focus. Kanzaki didn't disturb him and headed straight for the archives.

Among the materials left behind by former students, he found an inconspicuous photo album. He opened it to find photos taken by a student several years prior. On the bottom right corner of one page was a shot of the rooftop. The roof in the photo looked almost identical to the one he had just seen—a folding chair placed in the same spot, with a student whose face was obscured sitting on it, watching the crowd below. On the back of the photo was a line of small text: "You are never the only observer."

He returned the album to the shelf.

You are never the only observer. The sentence felt like a password, transmitted across the span of several years. Who was the person currently sitting in that folding chair on the roof? What were they watching? Was it a specific target, or the panoramic view of the entire campus? If it were the former, then the person being observed very likely included Sakura Airi.

When he walked out of the library, the sky was already turning dark. Most of the people on the playground had dispersed, but Sakura Airi was still sitting on the bench, holding her camera and looking at the photos she had taken that day. Kanzaki walked toward her.

"What did you capture?"

Sakura looked up. Without her hat, her purple eyes appeared exceptionally clear under the streetlights. She handed the camera to him. "...The light was especially good today. The cherry blossoms are almost gone, with only a few clusters of petals left on the canopy, just as the sunset pierced through them from the side." Her voice was soft, but when talking about photography, it was much steadier; no longer stuttering, her sentences were complete.

Kanzaki flipped through the photos. She had a talent for composition—not the standard, textbook-style structure, but a color arrangement imbued with strong personal emotion. Large areas of the frame were filled with the blank space of the pink sky, while the subject was a bare, withering cherry tree; the sunlight fell to the ground through the gaps in the sparse branches, and a small student stood within the cast shadow. The entire photo was like an unfinished sentence, making one want to continue it.

"You don't photograph people much."

Sakura lowered her head. "...People are hard to photograph. Their expressions are always changing; I never know when they are being real."

Kanzaki returned the camera to her and sat down on the bench beside her. The action made Sakura freeze slightly, but she showed no signs of discomfort. In the past, if she felt someone sitting too close, her body would instinctively lean a few centimeters in the opposite direction. Today, she didn't.

"If one day someone were to take candid photos of you, what would you do?" Kanzaki asked suddenly.

Sakura blinked. "...I don't think anyone would take photos of me."

"Hypothetically."

Sakura was silent for a moment, her fingers unconsciously fiddling with the camera's zoom ring. "If it were a candid shot... I suppose they wouldn't let themselves be discovered. If they were discovered, that would mean the other person wasn't very professional." She looked up at him. "Why do you ask, Kanzaki-kun?"

"Just wondering. Let's go, it's getting dark."

He stood up without saying anything more. Sakura packed away her camera and followed behind him. As the two walked out of the playground, Kanzaki glanced at the roof of the east school building. Behind the railing at the edge of the roof, there was a blurred silhouette. It was too far to see the face, but he could make out the figure's build. It wasn't Ishizaki, not Yoshida, nor any boy he knew.

The silhouette simply stood there, motionless, like a statue. Then, at the moment the sky turned completely dark, it turned and vanished.

Kanzaki withdrew his gaze.

After school on Thursday, he went to the rooftop for the second time. This time, he brought a lock—not to lock the door, but to test it. If he locked the door when he left and it was opened again the next day, it would prove that others were also frequently using this space.

He was in the stairwell inspecting the structure of the lock when footsteps suddenly sounded from below. Not just one person's footsteps; there was the sound of conversation. He put down the lock and leaned against the wall of the stairwell, letting himself fade into the shadows.

The footsteps drew closer. A man and a woman.

"...Are you sure it's here?"

"Of course I'm sure. I've been here several times already." The boy's voice—it was Ishizaki. That tall, yellow-haired guy who had been hovering around Sudo lately.

"Won't we be discovered?"

"Don't worry, nobody comes to this stairwell. The view from the roof is great, and no one bothers us."

The door was pushed open, and the two walked in. Ishizaki led the way, followed by a girl. He recognized her—she was from Class C, named Yamauchi, whom he had seen in the hallway a few times. The two went up to the roof, and their voices gradually faded into inaudibility.

Kanzaki stood in the shadows of the stairwell for a while, then silently pushed the door open and walked down the stairs. Ishizaki was using the roof for a date. That cigarette butt was likely his. He wasn't the observer; he was just a delinquent looking for a private space. That meant the real observer was someone else.

As he walked out of the school building, he ran into Horikita Suzune.

She was turning away from a vending machine, holding a can of black coffee. Seeing him, she frowned slightly. "You came out of the east stairwell? No one usually goes that way."

"Looking for a quiet corner to think," Kanzaki said. "You drink black coffee?"

"Sugar and creamer are superfluous. Pure things don't need extra parts." Horikita opened the can, took a sip, and looked at him. "You have the look of someone thinking about something extra."

"I was wondering if you could help me look into something."

Horikita raised an eyebrow, neither agreeing nor refusing.

"There is a regulation in the student handbook addendum—a student's personal behavior during their time at school is recorded. I want to know the specific form of that recording. Is it through terminal tracking? Surveillance? Or some other method? You're the person in class who analyzes the clauses most carefully."

"Surveillance. Library borrowing records, terminal consumption records, attendance data, and surveillance coverage in the gymnasium and public areas of the school buildings," Horikita said. "It isn't written directly in the student handbook, but it can be inferred from the comprehensive security regulations and privacy clauses."

"What about inside the dormitories?"

"There is no surveillance inside the dormitories."

"And the rooftop?"

Horikita paused. "The rooftop isn't within the public activity zone, so theoretically, it's outside the range of surveillance."

"Understood. Thank you."

Horikita glanced at him, not asking what he was investigating. "Next time you need my help, just say it directly. Beating around the bush is a waste of time."

She turned and walked toward the stairwell, the bitter scent of black coffee lingering in the air. Kanzaki Toru stood before the vending machine, inserted a few coins, and bought himself a cocoa. The rooftop being outside surveillance range—that was its true value. It wasn't a place for dates or sightseeing, but a private space where one could speak freely without being recorded. And the person sitting on that folding chair clearly understood this.

He held the cocoa and sat on the steps, drinking it slowly. In his mind, the rooftop was shifting from an ordinary setting into a focal point where various factions intersected: Ishizaki used it for dates; another person used it for observation; and in the future, he might need to use it for things that couldn't be recorded.

On Friday evening, Sakura Airi discovered a detail while organizing the photos she had taken that week.

"Kanzaki-kun," she called out to him, her voice sounding strange. "Look at this photo."

She turned the camera screen toward him. On the screen was a photo she had taken the previous afternoon—a faint figure was visible on the rooftop. It was a boy wearing a dark jacket over his school uniform, his face obscured by the railing. Sakura's voice dropped low as she continued to share her discovery: "I took this because the way the sunset reflected off the railing looked nice... I only noticed it after zooming in while organizing the photos."

"Can you tell who it is?"

Sakura shook her head. "The identifying features are blocked, but one thing is certain—his posture isn't relaxed; he's observing. His body is leaning forward slightly, and one hand is gripping the railing so hard his knuckles are white. He isn't someone just relaxing on the roof."

Kanzaki Toru was silent for a few seconds, superimposing the silhouette of the person he'd seen behind the railing at dusk onto the outline in the photo. The same position, the same posture. And the height and stance of the figure he had looked up at yesterday were more like those of a first-year student.

A first-year observer.

On the back of an old photo left behind last year, it was written: "You are never the only observer." And now, a new observer was in place. The rooftop was no longer just a location being used, but a vantage point where all the cameras were set up in front of the stage. Everyone was watching the actors below, while those actors remained unaware that someone was watching them from above.

He turned off the camera and returned it to Sakura. "Starting next week, if you go to the field to take photos, try to finish before dark."

Sakura looked up. "Is someone watching us?"

"Possibly. But keep taking your photos. If you notice someone watching you, don't make a scene; just change your position and keep shooting. Act natural, and you won't alert them."

Sakura listened carefully and nodded firmly. "I understand."

That nod was completely different from the shy, downward-glancing gesture she had shown at the start of the school year.

On Friday night, after Kanzaki Toru finished organizing his weekly notes in his dorm, he lay on his bed and opened the illustrated guide in his mind.

Sakura Airi's page glowed steadily, her favorability at 70. Next to her status bar, a new line of small text had appeared: "Intuitive sensitivity to threats increased." Horikita Suzune's page was becoming clearer, her favorability currently stable at 30, with "initial cooperation established." Kushida Kikyo's page remained a hazy blur, but the phrase in her title bar, "Boundary between surface and interior yet to be confirmed," was glowing faintly, as if about to be awakened by something.

In the bottom right corner of the final page, he noticed a tiny prompt appearing in an area that had previously been blank:

--"Rooftop scene unlocked. Conditions for new character triggered. Only one critical step remains until the next favorability reward."

Kanzaki Toru withdrew his consciousness. The observer on the rooftop, and the new subject about to emerge in the guide—these side quests were gradually unfolding. His gaze swept over the high walls of the school standing in the silence outside the window, and then he slowly closed his eyes.

No rush. This school had one thousand and ninety-five days; that was enough time for him to uncover the secrets on every page of the guide.