Ma En stopped at the first intersection and adjusted the deep red hat. He'd been conscious of it throughout — whether this meeting with Asuka would attract the enemy's attention. The monsters' surveillance capacity was formidable. His analysis of it: a kind of biological communal sense operating through the group, one that Matsuzaemon could channel without the individuals even noticing. It functioned like linking many separate cameras through an existing biological network — and those cameras could move.

He didn't believe the monsters, while living as human beings, were consciously aware of this capacity in themselves.

By now, Ma En had developed a considerable understanding of these creatures.

First: the reason they could embed themselves in every era, within whatever species flourished at the time, was that they achieved full mimicry of the group they chose to join. This was how they survived and grew. It was the source of their competitive strength. Because the mimicry was total, their own self-perception and self-awareness, during the period of integration, should differ very little from that of "humans" — until some kind of switch was pressed.

Second: Ma En didn't believe that once these creatures reverted to their own nature, they simply forgot everything they'd learned while mimicking their host species. Their powerful adaptability wasn't just expressed through integration; it was also expressed through genuine learning and growth within that integration. They didn't just passively inhabit — they absorbed and developed.

From where he stood, it was precisely because they shared stronger commonalities among themselves than any individual human group did that they needed some mechanism to diversify their individuality — and that individuality ensured the diversity of the species as a whole. At its core, this served the same function: the continuation of the species. Whether within a single planet or across the universe, across the generations of an incomprehensibly long timeline, facing a countless number of existential pressures, the degree of internal diversity determined the breadth of a species' survival range. It was a form of competitive fitness.

Third: when these creatures were not themselves — when they were functioning as members of the host species — their true selves were in a state of dormancy. They did not, in that state, act according to their own species' innate patterns, except in specific, particular circumstances. Ma En suspected those specific circumstances were something like human festivals and rituals: moments laden with accumulated meaning, cyclical events that carried weight beyond the ordinary.

The monsters' way of living appeared passive — as if without a host species to join, they would be unable to do anything at all. But Ma En had concluded this apparent passivity was actually their active choice. They had established their mechanism deliberately, and that mechanism had endured through time's elimination. Their way was their wisdom.

Humans were intelligent — or at least, on this planet, they regarded themselves as the most intelligent and competitive species, with some going as far as to say that when every other species on this planet was gone, the human would be the last to survive, the ultimate species. But Ma En was quite clear: no science had ever been able to prove that today's "intelligent human" would outlast other species that currently appeared far more vulnerable. And the reverse was equally unprovable.

Humans believed that "brain" and "intelligence" were the supreme weapons, because humans had survived and thrived by means of those weapons. This was a human advantage — one humans themselves could hardly be expected to deny. From that standpoint, all anti-intellectualist theories and behavior looked absurd. (Though one might acknowledge: anti-intellectualism might serve as a kind of corrective, a reminder, an insurance against evolution going astray.)

But from the perspective of species that hadn't chosen "brain" as their evolutionary direction — species that perhaps didn't think in these terms at all — was the human truly the "most fit"? Was the human choice truly the "best"?

Ma En didn't know. But he was certain: survival and competitive fitness did not require developing a brain. And intelligence was absolutely not confined to that roughly fourteen-hundred-gram, water-dense organic structure.

Seen from a specific angle: just as humans could create and use instruments to overcome their own limitations — which most considered the hallmark of human scientific advantage — so too could there exist peculiar species capable of borrowing other species' "brains" and "creations" to compensate for their own limitations. Theoretically, that was also a form of intelligence.

Who would still be alive at the end — across tens of millions, or hundreds of millions, or billions of years? Currently, only one answer held: only time would prove it.

And humans had existed for far less time than these creatures.

It would be irrational to regard the monsters as stupid, as passive. Yet to say they had no weaknesses was equally impossible. What Ma En had recognized — what might exist as a certain condition within these creatures — was perhaps simply a constant of their nature, not a weakness at all. Even so, a constant of nature could still be used.

As things stood, these creatures' individual states were not entirely self-controlled. And when they were in their own nature, their social hierarchy seemed extremely rigid — which explained how Matsuzaemon could exert control over companions no less intelligent than himself.

The exploitable point was precisely here: the creatures' unusual mode of living, their mode of growth, and the social structure that came with it — which Ma En could only describe as a "social structure," for lack of a better term — meant they were bound to have some unusual form of selection, of replacing the old with the new. Because their hierarchy was strict enough that higher levels could control lower ones — could control their thinking and sensation — this degree of thorough, comprehensive control, without any counterbalancing mechanism, would only diminish their survival capacity over time.

Think about it: if Matsuzaemon ordered all the monsters to their deaths, and those beneath Matsuzaemon's tier actually obeyed, they would be destroyed. That was contrasurvival.

Which was entirely inconsistent with everything the monsters represented as survivors.

So Ma En was completely certain: as a species, these creatures would never allow this situation to occur. Which also meant: Matsuzaemon's rank was likely very high, but his control was not absolute. His position was not absolute. There was definitely some mechanism ensuring that leaders of Matsuzaemon's type could not lead the whole species into ruin. And that mechanism was strong enough that even a so-called leader could not circumvent it.

These creatures were intelligent. Active. They had built a powerful mechanism to constrain themselves, and through that constraint had achieved extraordinary survival fitness. In this era they had chosen humans, chosen to survive by integrating into humanity — Ma En doubted whether many people had ever seriously considered what that implied.

He now believed it implied this: they were fundamentally incapable of bringing the full weight of their power down on humans. No matter how alien and frightening they appeared, they would not actively disrupt human survival and development — because that was their choice. He didn't know what role they had played across human history. But his estimate was strong: they would not voluntarily destroy the human social structure they inhabited. Not unless humanity itself decided to break its own old structures, satisfying some deeper developmental impulse.

They might be powerful accelerators of human society. But they were almost certainly not its decision-makers. What they decided was themselves — and their own internal mechanism constrained them, managed their renewal, screened for what might destroy them, ensured the species did not drift toward annihilation.

Ma En was moving quickly through a crossroads, thinking. Behind him, workers at the entrance to a high-rise building were hanging an advertisement for some health supplement, and its jingle was playing through a small speaker — the kind of thing you heard everywhere, cheerful and persistent. Ma En walked across the striped crossing, hat brim tipped down, the jingle following him for a moment.

He found it perfectly timed.

This mechanism — which he had reasoned into existence — was his opening. His odds.

Whatever these creatures would absolutely never do, if Matsuzaemon did it, Matsuzaemon was finished. And even if Matsuzaemon did nothing extraordinary, proceeding methodically along his plan, there was still a strong probability that the species' own internal renewal mechanism would eliminate him. He couldn't interrupt that mechanism — both his brief visible behavior and the story the Room 3 neighbor had told confirmed this: Matsuzaemon didn't have that capacity. Unable to accept elimination, he could only do other things — try to delay the process as long as possible, buy himself time.

It was like humans trying to extend their own lifespans.

Ma En thought this, freed one hand, pressed the hat lower, and moved with the crowd past a row of glass-fronted shops. This noisy city carried an enormous vitality, its colors vivid and sharp. It was the people walking these streets who produced that vitality, who made those colors real. But sometimes Ma En also felt that the city culled people, ensured its vitality and its colors endured.

Just as the Room 3 neighbor had said — not only did he and Ma En lack sufficient time; Matsuzaemon's time was also running short. The more violently Matsuzaemon moved, the more it proved he was fighting with his back to the wall, making his final struggle. And the more desperately he struggled, the greater the damage he caused to the social structure he lived in — and the higher the probability that the monsters' own survival mechanism would mark him for elimination.

Rationally and emotionally, Ma En felt he had some odds of winning.

August isn't only my deadline.

He touched the tip of his tongue to his upper lip. He stepped onto the hotel's entrance carpet. The hotel doors slid open as if to welcome him.

If the confidence he'd felt earlier had been psychological reassurance, the confidence he carried now came from rational, logical thinking.

There were still many unsolved mysteries — the Matchmaking God, for one. That was something of an entirely different category from the monsters. His logic and his knowledge might never solve that largest riddle. But the portion he could already reason about gave him more than enough momentum. He was eager to find the way to win.

Not thinking about the Matchmaking God, and considering only the monsters themselves — that was actually rather interesting. Their behaviors showed obvious internal logic and ongoing legibility. In contrast, trying to know the Matchmaking God was painful: he couldn't find an entry point anywhere. Its behavior was too opaque; its existence overturned all his frameworks. It was like how current scientific theory could predict the existence of black holes, but couldn't explain what black holes actually were. An infinitely small point possessing infinitely large energy — that "infinite" was, within science's framework, meaningless, because science required that nothing be truly infinite. Infinity was a false concept, a numerical joke, the inaccessible ultimate fortress. Closed and finite systems, necessary limits, irreducible base points — these were science's foundation.

He knew he couldn't entirely set aside the Matchmaking God. But he'd formed a working outline of his theory about the monsters, and still needed to supplement it, refine it, and put it into practice. And in moving from theory to practice, the Matchmaking God was probably unavoidable. He couldn't yet incorporate it into his framework as a variable. He knew he might have only a handful of chances — perhaps only one. He had to find the most critical point, and the right moment. One chance, maximum precision — that was what he was good at.

Ma En returned to his room. He put everything down, set the hat to one side.

He worked methodically: organized what he'd brought back, recorded his thoughts from the journey, organized those thoughts, confirmed for the third time whether anything had been missed or whether any new ideas had emerged. Only when the well of ideas ran dry and he could push no further did he set down his pen.

He picked up the hat.

He ran his fingers along the inner brim, feeling for the place where the texture shifted slightly, then tugged and pulled until something came loose. He drew out a small slip of paper.

He glanced at it. His pupils contracted slightly.

He hadn't expected this. But whatever warning it contained was not a joke.

The paper read: This is a warning to my future self — do not attempt to revert to your original self. The original Ma En has a fatal weakness...

Ma En stopped reading.

Even without continuing, he'd already guessed what that "fatal weakness" was. And it was one of the reasons he'd been hesitating all along. Reforming himself wasn't difficult — only painful, and he was confident he could endure pain. The real question was whether reverting to his original self was actually the right thing to do.

His original self had possessed extraordinary drive and formidable will when it came to pursuing the bizarre. Viewed dialectically from where he stood now, those qualities — which appeared to be strengths — could, under specific circumstances, become a weakness.

A fatal one.