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“Still, it’s stifling. Not surprising when we’re making heat in a place like this.”
“Ah—maybe my magic power’s finally running out. I think my power’s starting to drop.”

As we avoided the mummy and pushed deeper into the passage, the air grew steadily more humid.

My staff no longer had the strength to blow the dampness away, and the moisture that evaporated was turning into a heat and humidity like midsummer.

“Thirty minutes into the search… for your magic power, that’s good mileage. Or did your capacity increase while I wasn’t looking?”
“The latter, I’m sure!”
“I should take a page from that self-confidence of yours… whoa.”
“W-w-wait, careful, Master!”

Her foot slipped in mud that still hadn’t dried. She didn’t fall, but it had been close — the drying couldn’t keep up with our pace anymore.

“Master, should we head back?”
“No. At least let’s walk to the end of the passage. Thanks to the rain, most of the traps and golems aren’t functioning — I don’t want to waste this opportunity.”
“Mm, if only Daigorou wasn’t in maintenance right now…”

If Daigorou was carrying Master, it would make me feel a lot safer, but this wasn’t the time to complain.

Besides, if we forced Daigorou to operate in this damp, we’d just break him. And yet, if we kept going like this, I’d have to worry about Master’s stamina too…

“All right, at this point I’ll just have to give you a piggyback, Master!”
“No need. I can see the exit.”
“Wow, you’re right—wait, and it even looks kind of bright?”

At the end of the narrow, tunnel-like passage an open space came into view.

Unlike the dim corridor, it seemed as bright as daytime. Because of the backlight I could only see the scenery in a haze.

“Master, please stay back. I’ll go check if it’s safe!”
“You stay back. If something happens, I’m the one better suited to respond.”
“No fair—! Hey, wait a second!”

Ignoring my protest, Master strode forward ahead of me. She was so oblivious to her disciples worries!

I rushed after her as she vanished into the light, and then — as though wiping away the damp clinging to my skin — a fresh, cool breeze swept through.

“…W-wow.”
“This is… incredible.”

Master and I were both struck speechless. Beyond the passage lay a “village” far larger than the skeleton-filled hall we’d just left behind.

A blue sky spread overhead, and on the breeze came the sound of little birds singing somewhere far off — a tranquil scene.

Looking around, I saw houses of wood and brick and even fields. It was so idyllic I almost forgot we were still inside an underground ruin.

“M-Master? We didn’t take a wrong turn, did we?”
“Relax. This is still the underground. Look behind you.”
“Behind…? W-whoa, what is this?”

Doing as she said, I turned around. Sure enough, the entrance to the passage we’d come through was right there — but it stood all alone in this peaceful landscape like a pink door out of some cat-shaped robot’s cartoon.

“If you touch it, you’ll see. You just can’t see it, but there’s a wall around the passage.”
“R-really…? I can feel it…”

I gingerly reached out, and at once my fingers brushed against a smooth surface.

It was a strange sensation. The passage had been made of rough stone, but this felt like plastic. When I pressed a little harder…

“…Wait. Master, isn’t this not an illusion but a monitor display?”
“Monitor? …Ah, like the one used in Kyodaigorou’s control room.”
“Yes, yes! Look — if you press hard, the picture warps, see?”
“Easy for you to say with that monstrous strength of yours.”

I pressed the wall again right in front of Master. Around my palm the scenery began to ripple and discolor.

It brought back memories of when I was a kid, poking at my family’s TV and getting scolded.

This wasn’t an illusion — it was just a display projecting a tranquil landscape.

“…My strength isn’t enough. Even if I lean into it, I can’t reproduce that distortion. Must be built to last. Then, the sky’s light is fake too?”
“I think so. And if you look closely, even the plants on the ground are kind of strange…”

When I plucked a weed at my feet and rubbed it between my fingers, it crumbled apart like loose threads.

The texture felt closer to plastic than to anything alive—fake, though it looked perfectly real at a glance.

“Maybe the breeze is from air conditioning? And it’s so comfortable here—no humidity at all.”
“Which means the drainage system is fully intact. That explains the lack of flood damage. Most likely a residential block… though it feels very different from the rest.”
“This reeks of a secret being hidden here… Hm?”
“What is it, Momo?”

I had been striking a detective’s pose, hand to chin, when I suddenly caught something odd mixed in with the birdsong.

It was out of place. Not natural. When I strained my ears, I could definitely hear it—something hard colliding, metal scraping against metal…

“I’ve got it! Master, a golem is approaching! From above!”
“Yes, I see it too. You should take a step back—it’s dangerous.”
“Eh? Wait, wha—UWAAAH!?”

The very instant I looked up, a golem dropped from above and slammed into the ground right in front of me.
The sheer mass falling from such a height sent dirt flying, and since I was standing directly in front, I caught the full blast.

“Blegh! Pthh! Pffft! Master, you could’ve warned me sooner!”
“Ah, my apologies, my apologies. But never mind that—look ahead. You’ll be surprised.”
“Ahead…? …Eeeeh!?”

Of course, what landed was a golem, just as expected. But what stunned me was its appearance.

It had armor like a samurai, a long blade at its hip, and a towering frame well over two meters tall—an unmistakably Japanese-style robot design.

No matter how intimidating it looked, I could never forget such an impact.

“W-wait, what!? Why… why is Mr. Koutei here!?”
“――――Intruder presence detected. Biological signature identified… Error. Species: Human incompatible. Commencing elimination protocol.”
“Doesn’t sound like a warm welcome. Ready yourself, Momo.”
“Master, wait just—ugh, fine! I’ll handle this first and ask questions later!”

The Koutei look-alike drew its sword and fell into a stance, Master was already bracing for battle, and as much as I wanted to protest, there was no escaping it.

Confusion could come later. Right now, I had to deal with this doppelgänger.