Ma En ate with full attention, one large mouthful after another, and listened to the customers beside him talk. These were not politicians, not scientists, not public intellectuals — they were simply people with time on their hands, venting for the pleasure of it. In practice they had no great complaint about the way things were, and the moment they got busy, every word of this would be forgotten; they would never entertain the thought that something enormous was concealed behind these events. This was ordinary life — ordinary people, ordinary pleasures — and to keep this ordinary life intact, Ma En felt he still needed to push harder.

He lifted the large bowl and drank the broth in one go, then set it down gently on the counter. Asuka wasn't here; her father was busier without her, working with his back to the counter, not worried about anyone eating without paying. Ma En didn't call out. He reached into his pocket, pulled out some loose change, and left it weighted against the rim of the bowl. Then he picked up his black umbrella and walked out.

Outside the shop, he stopped.

He looked around slowly.

The surveillance sensation — building quietly for a little over a week — was no longer something he could dismiss.

At first he'd assumed it was his own nerves overreacting. By what he understood of the situation, those creatures wouldn't have surveillance methods this easy to detect. But the feeling had persisted, and grown, and he'd come to take it seriously. He didn't think their monitoring had degraded, and he didn't think his own sensitivity had sharpened to a new level — even though he'd never stopped studying the Seven Transmutations of the Profound Mystery Records, attributing this sensation directly to progress in that research felt instinctively wrong. He was more inclined to believe that something had changed on the other side: something hidden was operating differently now.

He had several theories, none of them provable. The surveillance feeling grew clearer by the day, and yet — as now — he couldn't locate the source no matter how he looked. His professional capabilities had not declined; the source simply operated by methods that were something else.

Or else: "the surveillance he couldn't detect" and "the surveillance he could feel" came from entirely different origins.

When it came to whoever was watching him from the shadows, Ma En had a list of suspects: Matsuzaemon was the most obvious, but beyond him — the Room 3 neighbor friend, the secret of Room 5, the mysterious voice he'd once overheard, Kamishima Kousuke. He'd examined whether any of these people's identities or behaviors might overlap, and the one that stayed with him, the one most difficult to read, was naturally Room 5. Something had perhaps existed there, but it had vanished from view. Vanished from view — and yet perhaps had not truly vanished.

He'd tried following the sensation on instinct. It seemed to work at first: without thinking, he knew which direction to move, and as the target area narrowed, he could even fix on a particular building, a particular alley, a particular open lot. But when he entered that narrowed range, the sensation became confused, lost definition. Within the zone where a lead ought to be findable, he couldn't confirm any specific target.

It was the same now. What he had been calling the surveillance sensation — no, that wasn't the right name for it anymore. If he concentrated, the feeling was less like being watched from a distance and more like something pressing against the back of his neck, nearly touching.

At times, he got an impression of movement: something like a transparent fish, drifting in the air, circling him slowly, staying always trained on his face — as if dissolving through the fabric of his clothing, gliding across his skin. A sensation that was faint but unmistakable, like something hungry, patient, studying him from every angle.

In the evenings, walking alone, the feeling was genuinely unnerving; he had a full appreciation now for the paranoia of people who suspect they're being followed. These days, whenever he left Room 4, there was rarely a moment that felt like he was alone.

Ma En tightened his grip on the black umbrella but made no further move. Every method he'd thought of had already been tried. Assuming the watcher was genuinely "formless and transparent," he'd also attempted to dye it visible — to use what he'd extracted from the Seven Transmutations to make the invisible show itself — but it hadn't worked. The right technique was still beyond him, or perhaps beyond the scope of what he'd managed to understand so far.

All he could do was reason from sensation and instinct, and sketch the shape of the thing in his mind: it was light, transparent — or perhaps extremely small. Many micro-particles massed together, fine enough to pass through the spaces between molecules, even atoms. Or a wave-form. Beyond particles and waves, it was hard to imagine what else it could be; but whatever its fundamental nature, when he tried to visualize it as a unified presence, a single consistent form kept emerging: something like smoke. Like smoke so thin it matched the density of the surrounding air and became indistinguishable from it. Capable of entering pores. Capable of drifting into the body itself.

Only an imagined form. But even as imagination, it was enough to be frightening.

In films and novels, the solution to this kind of creature was always romanticized into something simple: wave interference. In reality, even if it was some kind of wave or particle, disturbing its motion wouldn't simply cause its entire coherent structure to change in nature. The human body was made of particles too, and was subjected to interference at every moment — and yet the body continued to operate as intended. Against something not yet fully categorized, something that fell under the heading of "the strange and uncanny," he could apply scientific logic while simultaneously having to assume the upper limit of what it could do was very high.

That upper limit: as far as he was concerned, it could kill him on contact, ending everything before he even understood what had happened.

Even so, Ma En felt no panic — this was imagination and hypothesis. Since it hadn't acted, only watched, it must have reasons of its own. One could just as well assume that even if it had the ability to kill him on contact, it was constrained by reasons of its own and unable to do so.

There is a wide gap between cannot do it and can do it but does not. But sometimes, in effect, they are the same.

Most of the time, Ma En treated it as though it weren't there, and turned his attention to what he could actually handle.

He swept the black umbrella through the air. Nothing. He felt it — or imagined that he felt it: the thing swirling outward on the air displaced by the umbrella's movement, rising, hovering above him, watching from above.

—What a strange situation.

This thought crossed his mind more than once. Every lead gathered so far pointed consistently toward "plant" as the most intimately connected form to the strange and uncanny behind the Room 4 ghost story. The smoke-like form he kept imagining had no close relationship to plants. The only connection he could draw was something like spores — the slow-motion dispersal caught in nature documentaries, that fog-like cloud of particles spreading wide.

He didn't spend much time on this strange experience. Once the surveillance sensation had shifted from "pressing against his skin" to "dispersed in all directions," he continued on toward Sanchoumoku Park.

He boarded the bus. The invisible thing slipped in through the gaps in windows and doors. He stepped off. It followed, hidden in the small airflow his body made as he moved. He could always feel it — always. But as he drew close to the main entrance of Sanchoumoku Park, the sensation began to weaken.

It hadn't disappeared entirely. It simply felt more diffuse — as if the thing were spreading further apart, like an invisible mist settling around each tourist entering the park, following their breath into their bodies. Perhaps his own body too.

Ma En mapped this in his mind from what he could sense.

Whatever effect the thing might ultimately produce, it hadn't stopped him from entering Sanchoumoku Park — and that, to him, was a useful indication. He believed that once he was inside the caves, he would see more clearly what it actually was — because this strange watcher had also entered Sanchoumoku Park, hadn't it? It was here as well.

—The elements are converging.

He raised a hand, turned his hat brim slightly, and smiled.

Sanchoumoku Park had always been one of Bunkyo's well-known landmarks, one of the public spaces most frequented by residents; on this rest day, the tourist flow swelled further, people who had made the trip specifically to see the cracks and caves. Although the government had issued repeated prohibitions, and in ordinary times people broadly respected them — this time the situation was genuinely strange. People displayed an unusually fierce and collective curiosity, surging forward like a tide, leaving the authorities struggling. The police in Bunkyo were already stretched past capacity, as were departments elsewhere. When tens of thousands, hundreds of thousands of people poured toward these sites, it had long since exceeded what law enforcement could manage — and on top of that, post-earthquake relief and cleanup still demanded police support across multiple fronts.

Katsura-sensei had mentioned that the Japanese government was apparently debating whether to deploy the military — which Ma En could understand, given how genuinely strange these earthquake caves were, possibly constituting valuable historical heritage. But deploying the military to stop tens of thousands of civilians driven half-mad by curiosity? That would be absurd, and would become an even larger political incident.

What was unsettling was not what people were doing, but what was driving them to do it.

One person's curiosity was one thing. But when everyone was curious, and everyone was acting on it, and all of it had arisen so suddenly — that was something else entirely.

Many people believed this was the release of pent-up public emotion, the earthquake caves merely a trigger. Religious figures had waded in to take advantage, and there were plenty of people who wanted nothing more than to stir up chaos. Tracking all of them down would take time. And as best Ma En could see, the Japanese government's capacity for action had been operating slowly.

When religion became involved, the government's efficiency in Japan had always been limited — because it inevitably touched on the political struggle between the ruling parties. The Imperial Party had long been the most powerful supporter and most skilled exploiter of Japan's indigenous religious system; its greatest achievement had been leveraging traditional faith to win popular loyalty and halt Japan's reform. Japanese people held an unusually deep emotional bond with their native faiths, one that seemed to take precedence over advanced productivity and social relations. That faith was woven deep into their human relationships, and sometimes people placed these beliefs above their own lives and property. Ma En occasionally found it difficult to understand why this attachment persisted so stubbornly in the face of anything without scientific basis. Calling it part of Japanese culture was accurate enough — and still, Ma En thought, Japan was a very particular kind of place.

The Imperial Party had once boasted, openly: "Unless nine-tenths of the Japanese population were killed, the people's faith would not waver." Reform could not kill nine-tenths of the population. So reform had stalled.

And so the heightened emotions had arrived all at once, rippling through every corner of Sanchoumoku Park.

Many of the tourists were fully equipped — camouflage gear or outdoor jackets, camping packs on their backs — moving in groups, openly and loudly discussing how to breach the police line. Occasionally an officer walked past and looked the other way; Ma En could see that they were afraid. When the opposition was one or two people, they'd pile on. But at an average of more than ten agitated, entirely unpersuadable people per officer — there was nothing to pile on.

He could sense it again. Following the sensation, he scanned the crowd — every tourist here seemed wrapped in the same invisible thing that followed him. It encircled each person, its attention remaining fixed on him even through the mass of bodies. He didn't feel that any of the agitated tourists had noticed him specifically, though, mixed as he was among them.

They saw nothing. The cracks and caves occupied their entire focus; whatever they said, it circled back to the cracks and caves in the end.

—Frightening.

Ma En pushed his hat brim lower, until it seemed he could see only the ground ahead of him. His expression was flat, his pace unhurried. He fell into step behind a cluster of tourists moving deeper into the park — no matter how quickly they moved, he kept pace behind them at an easy, unhurried distance, and neither this group nor anyone they passed seemed to register the person following.

Only the invisible watcher never shifted its attention from Ma En for a single moment.

Ma En hadn't set foot in Sanchoumoku Park in the past week and more. His understanding of the cracks and caves had come only through news reports and secondhand accounts — in fact, he hadn't known the caves' exact location. As it turned out, this group pushing toward the restricted area was following the exact route to the deep-park section where the cemetery was located.

He'd seen that cemetery in Sanchoumoku Park himself, on his own visit, but what he'd seen had differed significantly from the paranormal footage on the tape Asuka had given him — a discrepancy that had kept troubling him. He badly wanted to go see the actual site now. But the group didn't push all the way to the cemetery — they stopped in a stand of trees.

Ma En positioned himself behind a trunk, tilted his head, and looked at the sky where it was cut into fragments by branches above him. A familiar cold, a familiar creeping atmosphere. It seemed to dilute the surveillance sensation further.

Ma En sensed it: the invisible thing was as out of place here as he was.

They were both uninvited guests, crashing the same door.

—Not the same system as those monsters?