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“We sure veered way off from that Ceren-something topic…”

Muttering with a small sigh was Cestlavie, who had been walking at the rear to avoid getting lost while placing talisman charms here and there throughout the labyrinth.

“Ch… Che… Chekhov’s gun? What’s that mean, anyway?”

Colin asked, blurting out a wildly off-base mishearing and a much more ominous phrase, at that. We ignored him for now and changed the subject.

“More importantly, why the sudden focus on a morning star?”

“Well, I mean… let’s just say it’s a commercial matter,” Coppelia replied, sounding like she had something stuck in her teeth, clearly dodging the question.

“???”
“It’s more like I received a transmission from the ether telling me that this is what I should be using. And as someone who can read the room, I’m going to go with this one. How about you, Lady Clara? Isn’t a blunt weapon basically a standard issue for holy people, alongside love and justice?”

Coppelia kept aggressively promoting her club weapon, but I couldn’t for the life of me understand what was driving her so passionately.

Just as I tilted my head in thought, her pumps stepped into a hollow spot slightly hidden from view, and in the next instant—

“DOOOOOOOOOOH!!???”

A trap disguised as a hanging stalactite triggered, and a barrage of spear-like spikes rained down on Coppelia at lightning speed.

“…Ouch. If the morning star hadn’t acted as a shield, that would’ve been fatal.”

From within the shattered debris that had taken a direct hit, Coppelia crawled out completely unharmed.

“So there are man-made traps too. I guess it makes sense if this place was originally the escape route from the Sant’Angelo Sanctuarium.”
“That was dangerous. My Princess was almost caught in it.”
“Everyone, please watch your step. We’ve dimmed the lights to avoid drawing attention.”
“Mrreoow~”
“Wh—!? Wha—!? Wha…!?”

While the rest of us had already grown used to this sort of thing and naturally ignored it, Colin was pointing at the totally unbothered Coppelia, rendered speechless. Hmm… I suppose this is actually the normal reaction. Maybe we really have grown out of touch with reality without realizing it.

I must be careful—so I reminded myself inwardly with a creeping sense of danger.

Incidentally, the light emitted by the phosphorescent rocks is quite faint. It’s just barely enough for someone with good night vision to make their way forward while keeping an eye on their footing.

Because of that, in a cave system like this, there are countless areas the light doesn’t reach, such as cracks, puddles, and traps like the one from earlier, all of which aren’t easily noticeable at a glance. If you let your guard down, it’s easy to stumble or get ambushed by a lurking beast emerging from a fissure. That’s why bringing additional light sources like lanterns is standard practice for navigating labyrinths.

Well, in my case, I can use the Light Magic Art, so we don’t have trouble walking. But that also means the enemy can see us just as clearly, so I try to keep the brightness and range of the light as narrow as possible. It’s not much, but it helps with avoiding surprise attacks.

We didn’t encounter much trouble after that, though we were attacked several times by small to medium-sized wastebeasts. At one point, we came across a corridor full of suspicious side-holes, so Cestlavie threw in a thunder talisman just in case. Sure enough, it was like dumping salt into razor clams: all sorts of creatures burst out, only to be smashed to bits by Coppelia’s bloodthirsty morning star.

“Still, is this *really* supposed to be a secret escape tunnel from the Holy Land? The place is so excessively elaborate that even a skilled adventurer would probably collapse before making it out.”

Even if you had templar knights for escort, they specialize in direct, fair combat. That kind of fighting is completely ill-suited for a labyrinth, where ambushes, sneak attacks, and deception are the norm. While strength in numbers helps, I doubt they’d be able to move a large group through a narrow escape route in the first place.

To that, Cestlavie, who used to be affiliated with the church and had been doing thorough research since coming to this era, offered an explanation.

“Apparently, it *was* just an ordinary escape tunnel originally. But thirty or forty years ago, the church brought in an independent alchemist to work on that artificial saint project. While doing research, the guy started dumping failed experiments, pouring out mysterious chemicals and waste oils, and in the end, he stole the research funds and ran off. To evade pursuit, he heavily restructured this place into a complete Dungeon… and then they just left it as-is. Or so the rumor goes.”

A story that sounded strangely familiar made me mutter:
“What a damn nuisance that guy must’ve been.”

“Truly,” Coppelia agreed with an expression like it was none of her business.

And then—

As we chatted idly, we arrived at a three-way intersection: a wide central path that led to the underground water source, and two side passages branching off to either side as supposed detours.

“No doubt the central one leads to the water source. Only there do I sense active movement from water spirits. As for the others… I can’t say. Neither water nor wind stirs in those directions.”
“A two-way choice, huh. But if we take a detour and end up caught in some trap, that’d be a real mess.”

Cestlavie frowned as he glared down both of the side tunnels.

“Ugh, typical cowardly plebeian mentality. Meanwhile, I’ve felt right at home ever since arriving here—like I was back at my parents’ house.”

Coppelia dismissed Cestlavie’s concerns with a smug laugh. But considering the dungeon was likely created and abandoned by the same person who built her, we had every reason to expect it wouldn’t be straightforward—something we’d learned the hard way.

“This is a problem. If only we had some sense of what lies down each path, or what kind of beasts are lurking, then we could at least make a more informed choice…”

As I was thinking aloud, I noticed Colin sneaking glances at me, like he had something he wanted to say.

“Is something wrong?” I asked.

At that, Colin drew a breath, reached into the frayed pocket of his jacket, and finally revealed a secret he’d kept to himself all this time.

“I… I have a best friend. He’s been with me the whole time since I arrived in this town.”
“Oh? That’s lovely.”
“My friend’s really good at reconnaissance, so I thought maybe I could send him ahead to scout the area and tell us what’s up ahead.”
“…Wait, your friend? What, you’re going to go call him now?”

Cestlavie asked, naturally suspicious.

But Colin tightened his grip on whatever was in his pocket and shook his head.

“No. He’s been here this whole time.”
““““????””””

All four of us—myself, Cestlavie, Coppelia, and Regulus—visibly tilted our heads in confusion as if question marks were floating over us. Colin, as if to say “seeing is believing,” pulled his hand from his pocket and slowly opened his palm to show us.

“Ki-ki-ki-kiii!” In Colin’s open palm sat a single pure white house mouse.

““““Haa…?”””” As we all stared at it with renewed confusion, Colin beamed proudly and held the mouse out where everyone could clearly see it.

“Let me introduce you. This is my best friend—”
“MREOOW!”

In a flash, with lightning speed, the winged cat Sechs darted in, snatched the mouse in his mouth, and disappeared behind a rock.

“A-, ALGERNON!!!”

Colin’s anguished scream echoed through the cavern as he lost his best friend in an instant.

***

#Author’s Note:#

Chekhov’s gun = A rule of foreshadowing that states any element introduced in a story must be used.

Most writers would suffer serious injury if shot by it.

As for the author of this work, merely having the barrel pointed at them would result in instant death—so please don’t aim it carelessly.