Mai Sakurajima was a celebrity; every student at Ichinan High School knew that. No, probably somewhere between seventy and eighty percent of the entire country's population knew who she was. She was a true celebrity, to the point where it didn't feel like an exaggeration to say so.
She debuted in show business as a child actress at the age of six. She began with a morning drama that boasted ratings and popularity on par with major hits, becoming an overnight sensation. From then on, after her explosive start, she appeared in numerous films, dramas, and commercials, achieving such fame that literally not a single day passed without her appearing on television.
Of course, two or three years after her debut, the phenomenon of "Sakurajima Mai in everything" lost some of its momentum. Still, rather than fading away, she began receiving even more offers thanks to her acting talent. Among the many actors who vanished after just one year, her career remained solid even after she entered elementary school. That alone was already very impressive, but she also experienced a second rise. At fourteen, Sakurajima Mai had transformed into a beautiful young woman with an almost adult appearance, and with the film that was showing at the time, she quickly regained attention. In just one week, magazine covers were completely dominated by her smiling face.
Many young boys had their hearts stolen by her…
Her popularity was once again heading toward its peak. However, while this was happening, she suddenly announced that she would be taking a hiatus from her activities. It was shortly before she graduated from elementary school, and no specific reason was given. Since then, two years and a few months had passed.
Naturally, when the students at Ichinan discovered that Sakurajima Mai attended the same school as them, they were surprised and simply thought that celebrities really did exist in the same world as they did.
And, as always, many rumors emerged. That she was involved in prostitution. That she was having an affair with her producer. Things like that…
…even though she was still just an elementary school student at the time.
Information spread and was shared in an instant on the internet. And even when there was no basis whatsoever… the recipients hardly cared about its truthfulness. They just wanted to talk about it, make jokes, find it funny or entertaining, or simply satisfy themselves with it.
Her predecessor had never spoken to her personally back then. Despite hearing the rumors, he had been too focused on soccer and chasing his dream. He didn't care about actresses; even though he had seen Mai countless times on television and recognized her beauty, his heart hadn't been stolen the way so many teenagers' had…
…And now, she was right in front of his eyes. The eroticism from her shoulders down to her breasts had been laid bare for him to see, and Mai placing her hand on her cheek emphasized her cleavage. She had left behind a pleasant fragrance, and the murmur of her voice had been audible only to him. The entire conversation between the two of them, and that feeling of connection he felt with the other girls, made everything indescribable…
Mai hesitated for a moment, her fingers still pressed against her flushed cheek. The gesture was almost unconscious, as if she were trying to hold back the heat rising to her face. Her amethyst-blue eyes, filled with a mixture of exhaustion and something that looked like genuine surprise, met Isagi's once again.
"It's… complicated to explain," she murmured, her voice low enough not to echo between the shelves. "It's not something I can put into a few words. Nor something I completely understand myself…"
Isagi didn't reply immediately. He slowly shifted his gaze, scanning the surroundings with the same analytical calm he used on the field. The tables were occupied by students hunched over books or laptops, a staff member pushed a returns cart, an elderly man read a newspaper in the opposite corner of the room. No one was looking in their direction. No one seemed to notice the bunny girl talking to the boy who had taken off his cap—speaking of which, he put it back on to avoid any trouble…
He turned his eyes back to Mai.
"We have time…"
Mai blinked, let out a short sigh that was almost a soundless laugh, and lowered her hand from her face. The black leotard followed the subtle movement of her chest as she took a deep breath, trying to compose herself.
"…You really are different," she murmured, more to herself than to him. Then she raised her gaze again, this time with a more open, almost resigned expression. "Fine. I'll tell you what I can. But if you run away thinking I've gone crazy… I won't blame you."
Isagi leaned back in his chair, crossing his arms on the table, body relaxed but clearly attentive.
"I've seen a lot of weird stuff these past few months," he replied, the corner of his mouth lifting in a minimal smile. "A senpai dressed as a bunny girl in the library who's invisible to people doesn't even make the top five. Go ahead."
Mai sighed and decided to start explaining.
"I noticed it on the first holiday of this month…" In other words, a week earlier, on July 3rd, Marine Day. "I went to the Enoshima Aquarium on a whim."
"Alone?"
"Is that a problem?"
"I just wanted to know if you had a boyfriend."
"I've never had one." Mai pursed her lips indifferently.
"Hehhh."
"Is there a problem with me being a virgin?"
Mai looked at Isagi provocatively.
"…"
"…"
Their eyes met. Mai turned bright red instantly—pure red, all the way to her neck. Apparently she was embarrassed by the word "virgin," even though she had started it.
"Ahh, I have a rule about not worrying about that kind of thing."
"O-okay… anyway! I noticed that no one was looking at me at that aquarium, which was full of families."
Mai's slightly grumpy expression made her look younger and more adorable. Since he had only seen her adult appearance before, this was a new experience in many ways. If he pointed that out, he would derail the conversation again, so Isagi kept it to himself.
"At first I thought it was just my imagination. It's been two years since I was active, and everyone was distracted by the fish." Her tone gradually grew more and more serious. "But it became clear when I went into a café on my way home. No one greeted me, and I wasn't shown to a seat."
"Was it self-service?"
"It was a traditional café, with counter seats and only four seats at each table."
"So you went there in the past and got banned?"
"No way that's it."
Mai's cheek twitched in anger and she stepped on Isagi's foot under the library table.
"Senpai, your foot."
"What about my foot?"
Mai asked seriously, truly acting as if she didn't know. He really reflected right then that she was a professional.
"Nothing, I'm just happy you're stepping on me."
He meant it as a joke, but Mai pulled back and moved as far away from Isagi as she could.
"It was a joke."
"I felt at least a little seriousness in it."
"Well yeah, as a guy, I'm happy to have a beautiful senpai paying attention to me."
"Right, right, I'm continuing now, so be quiet. Where was I?"
"You were talking about how you got banned from a café."
"You're going to make me angry." Mai's gaze sharpened at that, and no matter how he looked at it, she already seemed mad. To show his apology, Isagi mimed zipping his mouth shut, and Mai continued with an unhappy expression. "Even when I spoke to the staff, they didn't respond, and none of the other customers noticed me either. Obviously I was shocked, so I ran back home."
"How far?"
"To Fujisawa. But nothing happened when I got there. Everyone looked at me the way they normally would—surprised to see 'Sakurajima Mai.' So I thought it really had been my imagination, but… I was curious, so I started checking if it happened in other places."
"And the bunny thing?"
"In this outfit, if people could see me, they would stare so much there would be no room for doubt."
That was exactly right; his reaction proved how effective it was.
"So in other places… you're basically losing your presence and becoming invisible in various places quickly?"
"That's right. Now I'm just waiting until I become invisible to the whole world."
"It seems like you're enjoying this, Senpai, even though you're having such a strange experience."
Isagi gave his honest impression. Mai didn't seem particularly sad about it.
"Well yeah, it is fun."
"Are you sane?"
He turned a questioning look toward her, not understanding what she meant.
"I've always been the center of attention, haven't I? Living under everyone's gaze. So when I was little, I made a wish to go to a world where no one knew me."
She didn't seem to be lying, but even if what she said was an act, there were enough reasons to believe her. She was an actress who had managed to become a real actress after starting as a child actress.
While they talked, he noticed her eyes move toward one of the newspaper pages being read by the elderly man not far away. It had an advertisement for a novel being adapted into a film. The lead actress was a popular woman who had recently been promoted, and he thought she was about the same age as Mai. She was probably thinking about trends in show business, or maybe feeling nostalgic? No, he had the feeling that wasn't it. He thought Mai's eyes, which seemed to be looking into some distant world, held some burning emotion. Put another way, it looked like some kind of regret or attachment.
"Senpai?"
"…"
"Sakurajima-senpai?"
"I can hear you." After a blink, Mai glanced sideways at Isagi. "I'm happy with this situation. So don't interfere."
"…"
Isagi stayed silent for a few seconds after her words.
Then he let out a small sigh through his nose.
"…There's no way I won't interfere."
Mai's amethyst-blue eyes narrowed immediately.
"What?"
Isagi tilted his head slightly to the side, as if organizing his own thoughts.
"I don't know how to explain it properly…" He continued, voice low but firm: "But… from the moment I first saw you…"
He paused briefly.
"…I just couldn't ignore you."
The air between them seemed to grow heavier.
Mai blinked; her heart raced inexplicably.
"…And," Isagi added, watching her with that almost uncomfortably direct attention: "I'm almost certain you felt something too."
Silence.
Mai's face turned red.
"W-What kind of hasty conclusion is that?!" She fired back immediately, straightening her posture like a senpai about to deliver a formal scolding. "Don't talk like you understand everything just because you observed me for five minutes!"
But her voice… faltered slightly at the end.
Isagi noticed.
"…If that wasn't the case, you wouldn't still be here."
The words hit home.
Mai opened her mouth and closed it.
Because, irritatingly…
He wasn't wrong.
She could have left at any moment.
She could have ignored him.
She could have treated him as just another stranger.
But she didn't.
"…You…" Mai murmured, trying to regain her composure. She lifted her chin, assuming her usual superior-senpai posture. "You're pretty full of yourself, you know that?"
Isagi shrugged and spoke calmly: "It's part of my desire to be more selfish…"
"You believe the crazy things I've said?" Mai asked, looking at him deeply.
"How should I put it… I know about this kind of thing."
"…"
"It's Adolescence Syndrome."
Mai's eyebrows rose in surprise.
He hadn't heard of anyone becoming invisible, but there were plenty of rumors about 'being able to read minds,' 'seeing the future,' 'swapping bodies with someone,' and other mysterious occurrences like that. If you looked in those kinds of discussion forums, there were many more.
Normal psychologists assumed it was a sign of instability and ignored it completely. Self-proclaimed experts called it a new type of panic attack caused by modern society, and common entertained groups of people who monitor others' thoughts had opinions like 'it's a form of mass hypnosis.'
There were also people who called it a mental illness triggered by the stress caused by the gap between an inhuman world and a person's ideals. The only common point was that no one took it seriously. Most adults dismissed it as 'just your imagination.'
Amid this irresponsible exchange of ideas, although he didn't know who first said it, strange occurrences like what was happening to Mai came to be called "Adolescence Syndrome."
"Adolescence Syndrome isn't just a common urban legend?"
Mai was exactly right; it was an urban legend. Normally, no one would believe it, and everyone would have the same reaction as Mai. Even if they themselves had experienced something strange, they would think it was their imagination and wouldn't accept it, because they lived in a world where such things weren't supposed to happen. But he had come to believe in all of it after encountering a god in a temple; he had come to believe in everything that had a supernatural rumor in this world…
"It's real…" Isagi replied simply, without beating around the bush. "I know because… well, I've seen similar things. Not exactly like yours, but… inexplicable. Things science ignores and adults call a 'phase.' But to me, it's just life being stranger than we expect."
Mai fell silent.
It wasn't just surprise. It was something deeper, harder to decipher. A silence filled with thoughts crossing too quickly to be organized. She blinked slowly, her amethyst-blue eyes flickering as if searching for an answer that simply didn't exist.
For a few seconds, the only sound between them was the faint hum of the library's air conditioning.
Then, suddenly, she stood up.
The movement was smooth yet unexpected. The leotard caught a discreet line of light as she averted her gaze, as if afraid to face what Isagi had just said.
"…I don't know what to say." She murmured in a low voice, almost too fragile to match her upright posture. "And… I think I don't need to answer right now."
Her fingers slid lightly along the side of her arm, as if seeking support in herself. There was something melancholic in that small hesitation. A living contradiction between the confident Mai who seemed capable of facing any audience and the Mai who, in that instant, didn't even know how to face her own existence.
"Anyway…" She continued, taking a deep breath. "I like the situation as it is. Not being seen. Not being recognized. It's… comfortable. It's a rest I've never had."
Isagi watched her in silence.
Her eyes finally returned to his. There was sincerity there, but also a hint of something he couldn't name. Something like fear. Something like… resignation.
"…So I don't want to change it." She concluded, with a smile too small to be genuine. "At least for now."
She tilted her head slightly, stepping back. Her long hair cascaded over her exposed shoulders as she adjusted it almost automatically.
"It was nice talking to you." She said, with a calm that seemed rehearsed, but her posture couldn't hide the reluctance. "I hope you have a good read."
She turned to leave, passing the last row of tables, her movement graceful even in the silent environment. Her hand touched the sliding library door.
And it was there, in the exact instant she began to walk away, that Isagi rose from his chair. He simply followed his selfish desire…