In the dark of the forest, in the scattered organs and pooling blood and the dense, iron smell, in the pit where the thick, gnarled roots showed, Ma En and the neighbor friend stood looking at each other. A low, final declaration rang out in the night wind. Below their feet, the spilled blood, the organs, the fresh flesh — as if something invisible were pulling and lifting it — or as if the pieces themselves were alive — began drifting back toward each other, slowly gathering.

"Look. It's coming back together." The neighbor friend's eyes shifted toward the scattered remains and he said it without surprise. "This is a sight most people never get to see. As long as blood and flesh remain, it restores quickly. If nothing was left, the body would grow back just the same — the way this tree is sprouting new branches. Friend — want to try burning it?" He pointed toward Ma En's pocket. "You have a lighter, don't you? Try it. One practical demonstration beats all the argument, and then you'll accept it."

"No need." Ma En took a cursory look at the blood and flesh eerily converging, his expression somewhere between grim and entirely blank. "You're telling me not to waste time on how to kill these particular monsters, right? I understand already. They're not all unkillable — just very inconvenient. And we have no time. Right?"

"Hm-hmm. You're finally getting it." The neighbor friend's voice grew quieter. "However much I talk, if you haven't accepted it from the gut, it's useless — you'd just keep spending time and energy on the regeneration problem. In the past I did the same. Wasted too much time."

"After all this time, do you now know how to kill them completely?" Ma En turned the question back.

"I can kill them completely now. But what would be the point? Even I can't kill all of them. And on top of that, right now I still have to stay hidden, and even showing you all of this is something I've been doing on edge the whole time." The neighbor friend said, with a hint of self-deprecation that carried no heat. "Let's go. Now that you understand, let's go. The sun's about to rise."

With that, the vines extended again, winding around Ma En like tentacles. This time Ma En didn't struggle, didn't feel surprised. He'd started getting used to this way of being transported. The vines were flexible to a degree that made the body uneasy, psychologically and physically — but they didn't bring danger to his life. Not right now, at least. Knowing this brought a quiet.

He'd also thought about whether, in some future circumstance, he might end up in conflict with this neighbor friend, or with something similar. How he'd deal with these vines in that case. The thinking had no conclusion. However he approached it, the vines and everything they expressed about the neighbor friend's overall monstrous form presented a kind of integrated power that no individual human could stand against — like a person with bare hands facing a hungry predator. The neighbor friend's manner, on a good day, was more savage and brutal than any predator.

Ma En would feel fear when near the neighbor friend. He hadn't shown it, but he wouldn't lie to himself about it.

Going head-to-head with this man — even knowing his own physical capability far exceeded most people's — he didn't feel he had even a thirty percent chance of surviving.

What if the black umbrella were in his hand? Would the result be different?

Probably not much. A bit longer. But it would still end in running, or dying if he held on to the end.

In his heart, he'd already accepted it: in the face of this kind of bizarre, monstrous form, he was unquestionably the weaker party.

Which meant, exactly as the neighbor friend said: no choice but to overcome the strong as the weak. If this world had no room for that kind of miracle, both of them were finished. Fortunately, "overcoming the strong as the weak" didn't mean "direct combat." It didn't mean using his own raw strength.

He kept compiling everything he knew, and in a short time had formed several initial frameworks. But the highest probability among them was still below ten percent.

"...I can feel your mind going at full speed. Aren't you tired? Everything that's happened since this morning has been outside your expectations. You've been thinking the entire time, without a single pause. What are you even thinking about?" The neighbor friend gathered Ma En up, jumped out of the pit — apparently about to leave — but suddenly asked this. "What kind of person are you? The old you I could understand — more like a monster. But the current you is plainly more human — and ordinary people's minds don't have this kind of resilience—" Even as he said it, he looked again at Ma En's injuries.

"Me? Just a schoolteacher." Suspended in the vines, swinging in mid-air beside the neighbor friend, Ma En met the scrutinizing gaze and simply smiled politely.

"No. I'm asking what you were before Japan. You're not local." The neighbor friend's ugly face leaned closer, nose twitching, as if he could genuinely smell something unusual there. Eyes shifting, he said: "You're definitely not normal. There's a strange quality about you. I sensed it when you first arrived."

"A quality?" Ma En turned his head and sniffed his own shoulder. "What quality?"

"Not a normal smell. Something not in ordinary understanding. When you first came, I caught a faint trace of it. Maybe I was drawn to that from the start — maybe that's what made me think you... no, maybe it's precisely because you carry that unusual quality that you became the chosen one." He murmured, sinking into the pleasure of his own speculation, apparently not actually expecting Ma En to answer. "Strange, truly strange. You have something that draws me, draws these monsters, draws Hirota Masami. Maybe even if you did nothing at all — just sat quietly — they'd come to you. Yes, yes, exactly — like a magnet... like fate..."

"...What are you talking about?" Ma En interrupted. "Before Japan, I was just a civil servant."

"Ha? A civil servant?"

"Yes. At the postal service."

"The postal service?" The neighbor friend's expression twisted. "You're saying you're a mail carrier?"

"No — a civil servant at the postal service. Different from a mail carrier. Why does everyone assume postal service means mail carrier? The postal service covers a very wide range of work. Many different roles."

"...What are you talking about? Postal work is delivering mail, isn't it?" The shadows on the neighbor friend's face seemed to deepen.

"Delivery is one part of the work. The smallest, the most ordinary, the most widely understood part." Ma En answered evenly. "There's considerably more beyond that. The broader work — ordinary people don't need to know about it. And some of it has confidentiality requirements."

"...What kind of postal service has confidentiality requirements?" The neighbor friend felt his own head going slightly fuzzy. "I've never heard of any such thing."

"That's because you're not well-informed, my friend." Ma En's courteous, untroubled smile was beginning to irritate the neighbor friend. Almost without thinking, he tightened the vines around Ma En's body.

"You're hurting me." Ma En said without changing expression.

"Oh — sorry." The neighbor friend realized what he'd done, and the tightening immediately eased.

"Leaving this corpse — this monster — behind. Is that really all right?" Ma En shifted the subject.

"What's the problem? It will revert to the appearance of the person it was before, leave the park on its own, re-enter the world. It will have a fabricated memory that holds together — something like spending a night wandering through the park. No one will suspect it. No one will think it was ever a corpse. And the police will no longer have a legitimate reason to keep targeting you." The neighbor friend continued: "It's over, my friend. Beautifully over. No corpse, no death, nothing — everything is normal. For people, everything is peaceful. Everything is ordinary."

"But we dissected it right when it was born."

"It will think that was just a nightmare — like a person having a nightmare." The neighbor friend said, without inflection. "Without some exceptional circumstance, it won't even know it has become a monster. Look — even under a medical examination, it's no different from a normal person. It will live on, die as humans die from accidents, die when its natural lifespan runs out — but no one will ever be able to confirm whether it has truly died."

"What a remarkable kind of monster," Ma En said with genuine feeling.

"Remarkable? Yes, remarkable."

"To have chosen blending into humanity as a way to survive."

"That is their way. This strategy has carried them through countless mass extinctions." The neighbor friend said. "When humanity perishes in the next one, when new species emerge, they will persist in exactly the same way. Perhaps for them, 'the rise, flourishing, and fall of humanity' is nothing more than a fleeting moment."

"That's quite the poetic take." Ma En hadn't particularly meant it as a barb — but the neighbor friend caught an edge in the words. He clearly wasn't comfortable with it. With a sharp yank of the vines, he launched himself into the night sky.

The force tore at Ma En's body, filling his mouth with open air. He heard the neighbor friend's contemptuous laugh ring out: "Enjoying yourself with all those clever words?"

Ma En clamped his mouth shut. His body ached everywhere — but his spirits were considerably better than before. Now he could finally let go of these "ordinary" monsters and seize hold of what actually mattered. The Room 4 ghost story was bizarre and strange — but once he separated the real priorities from the confusing loose threads, he could see more clearly what needed to be done, and how to do it.

The neighbor friend, for all his mental chaos, strange personality, and unpredictable instability — it had to be said: without his help, Ma En would still be stumbling around in the dark. From that alone, Ma En felt lucky. In this bizarre affair, luck was the best thing he could have found.

The return journey was faster than the outward one. The city's liveliness had reached its lowest and most hollowed hour — the neon still spinning and flickering, but the streets around them strangely quiet and cold. Whatever had been alive the night before had ended; what would live through the day hadn't started. Then as the two of them dropped into the courtyard of the apartment building, the world seemed to shrink down to this small space, and nothing stranger happened the rest of the way.

Before the sky had begun to brighten, the neighbor friend and Ma En were back inside Room 3. They came in through the window, the same way they'd left. The moment they returned, the vines spread again, covering all the rooms. The window closed. The curtains were drawn. The dim interior of Room 3 seemed to reverse time — light, smell, sound, every perceptible quality returning to exactly what it had been when Ma En first stepped through the door.

He almost fell into the illusion: he'd never left Room 3. He'd never leaped through the night sky. He'd never entered Sanchoumoku Park. There had been no body, no monsters. He'd just been standing here, from the beginning, for what felt like only a few minutes.

But he knew it was only an illusion. His blood and wounds said otherwise.

The wound on his forehead had stopped bleeding, scabbed over — but Ma En still couldn't forget: the uncanny force from before, which had seemed to press through brain and skull alike. He picked up his briefcase from beside the sofa, checked its contents, then turned back and thanked the neighbor friend: "Tonight was a real imposition."

"You're leaving?" The neighbor friend only asked this.

"Need to shower." Ma En said.

"What about Hirota Masami?" The neighbor friend asked.

"I'll have to face her eventually, won't I?" Ma En answered, then, after a moment, reversed the question: "How did you face Miyano Akemi, in the beginning?"

"...I was in love with her." The neighbor friend said only this, and then went quiet — as still as a carving, settling onto the sofa, as if falling into a memory from somewhere long ago.

Ma En didn't look back. He didn't ask further. He didn't hesitate for even a moment. Briefcase in hand, he moved toward the door.

"Wait."

The neighbor friend's voice came from behind him.

Ma En stopped. He turned, curious.

Across from him, a long blurred shape materialized in the darkness, and came sweeping through the air. Ma En caught it by reflex, before it struck him. The weight hit his palm — heavy, dense, and immediately familiar, in a way that reached deeper than memory. Like something that had been buried in him, long accumulated, slowly rising to the surface now.

"You threw it away once. You decided you didn't need it anymore. But I thought you'd need it again. So I picked it up."

"...Thank you."

Ma En could see clearly now. In his hand: his old partner, the one he hadn't seen in far too long — the black umbrella. Heavy and worn, its color and shape exactly as he remembered. The hardness and temperature of it when gripped sent something moving through him that felt almost like a spoken message — something warm and long overdue.

Long time, old partner.

"I said — I prefer the current you. You're a good person, my friend." The enormous shape pressed into the sofa said.

"I believe the old version of me wasn't a bad person either."

"But the old you couldn't let me relax." The shape answered.

"Maybe that was just your impression."

"Not necessarily. The old you was a hedgehog — always looked like he was about to fight."

"..." Ma En was quiet for a moment. Then he raised the black umbrella in the dim room and said: "Friend — maybe the current me is different from the past, as you say. Maybe something at the most basic level has changed. But believe this: even now, I can still fight."

Because—

When a person is forced to fight, the fact that they've become a different person never means the fight stops being necessary. If a certain fight has always accompanied this person — the will to fight doesn't leave just because they've changed.

"When a fight comes — it makes no difference whether the person facing it is ordinary or not." Ma En said with certainty.

Only silence from the sofa.

"I've always been fighting." Ma En turned back to the door and pushed it open. Corridor light slid in like mercury through the crack, illuminating one corner of the entryway, one half of Ma En's body.

His silhouette — halved between light and dark — seemed to squeeze itself out through that narrow gap.

"Then keep your weapon. Don't lose it again." The voice from behind him seemed to come from somewhere very far away.

"...Needless to say." Ma En answered.

When the door closed behind him, his shape dissolved into the light on the other side.

Ma En stood in the corridor — briefcase in one hand, black umbrella in the other, blood across his clothes. The corridor's flat, indifferent light fell on him without managing to illuminate all of him. The blood on the dark suit was a dull reddish-black. But at this moment, it was the slightly loosened deep-red tie that caught the eye more than anything else — as if everything that constituted him, body and soul, had been distilled into that strip of color.

He looked toward Room 6.

The thought in his mind was entirely different from what it had been a few hours ago. He no longer felt that avoiding Hirota-san was the correct choice. In the Room 3 neighbor friend's assessment, Hirota-san was involved in the Room 4 Ghost Story — but she had no particular bearing on the act of killing Matsuzaemon. And yet, just as the neighbor friend had sometimes let slip traces of a past he still carried — how important Miyano Akemi had once been to him told Ma En exactly how important Hirota Masami was now.

If Matsuzaemon had killed Miyano Akemi, he would very likely, at the last moment, also try to kill Hirota Masami.

Whatever she actually was — given that the only course of action available was to move against Matsuzaemon — Ma En wanted her to survive. Just as all the other monsters, after Matsuzaemon was gone, would simply continue living their ordinary lives. If they could live, why couldn't she?

He didn't believe humanity was so weak that killing Hirota-san was necessary to remove the threat. Perhaps, measured against the vastness of the cosmos, humanity was small — like an infant yet to leave the cradle. But Ma En thought the neighbor friend had said one true thing: each individual was not a monster, but humanity, as a species, was this planet's most formidable creature in this age — without equal. In growing, this creature should develop enough capacity and breadth to eventually make room for a species that had arrived before the planet's civilization even began.

No, more than that: if humanity, moving forward, couldn't even manage this — it would only prove that humanity had always been and would always be fragile.

How much a creature could contain — didn't that speak from the other side to where its limits were?

Ma En wasn't worried about humanity at large. He didn't have the ability to worry about it. He only needed to worry about himself, about the people immediately around him. And that, he felt, was already exactly the weight he had to carry.

With this in mind, the memory of why he'd left his homeland — ice-cold information until now — in this moment ceased to be cold. It became something real and brutal and warm, flowing quietly through his body.

In the warmth of that resolve, he pushed open the door to Room 4.