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Cestlavie, with Martha’s knife pressed to his throat, and the demon boy—expressionless and glassy-eyed even now—held by the scruff of the neck by Dan. Faced with this double hostage situation:

“ “Watch out!” ”

Both Cestlavie and I—despite the blade at his throat—shouted at the same time.

“Hm?” Martha frowned and glanced at Dan for instructions, but before he could even open his mouth, I moved on reflex. I tackled Coppelia from behind, pinned her to the floor, twisted her right arm back—yes, it wasn’t the most graceful position—and straddled her, restraining her completely.

“Hebuh—!”

Immediately, like someone whose hiccups had been forcefully cut off, Coppelia let out a strangled grunt, and the weapons that had been reaching critical mass all over her body were abruptly canceled mid-deployment. Her body began to vibrate erratically like a broken appliance—Dan and Martha were visibly recoiling at this point—as blasts of hot air jetted out from various gaps in her frame, accompanied by billowing steam and white smoke.

Her short maid uniform flapped wildly, as did the bangs over my eyes.

This was the mysterious “maid skill” that let her pull out scissors, dusters, hand mirrors, and more from who-knows-where when needed. According to Beatrice, the head housekeeper at the Brandmüller estate, a maid’s skirt is full of secrets. And sure enough, I may have glimpsed more than I should’ve for just a split second. *Holy fig leaves and flying turtles…*

“What the hell is this supposed to be?!”

Dan snapped out of it and barked in disbelief, his voice now laced with murderous intent.

“…Lady Clara. Is this some new kind of play?”

Coppelia asked, totally off the mark. And Martha, upon hearing that, gave a quiet “Ah…” of realization—which, frankly, stung a little—but I ignored it. Still holding Coppelia down firmly, I declared:

“I simply neutralized the most dangerous thing in the room—for everyone’s safety!”

“What… are you talking about…?”

Dan, unaware of just how dangerous Coppelia could be, stared at me with growing suspicion.

“??? Wait, isn’t that demon kid the most dangerous one here?”

Still pinned to the floor, Coppelia looked around in confusion and pointed at the demon boy Dan had by the throat.

“What… did you say?”

Dan frowned, and to be honest, I was a bit surprised myself. I had assumed that, being Coppelia, she’d ignore the hostage’s safety and launch a no-questions-asked assault on Dan and Martha—something like a rocket punch, maid beam, or an infinite sweet bun cannon from her forehead. That’s why I stopped her.

“Coppelia, just to confirm—can you rank the people in this room by level of threat, from most dangerous to least?”

“Yes. Number one is Lady Clara—danger level: seriously infinite. Next is the demon child who’s about to self-destruct; I’d say their danger level is around 135,000. Then there’s the dumb commoner lagging far behind at 1,600, the balls-for-brains guy at 550, and the bimbo at 120. Anything below single digits gets rounded off.”

Even though my question was sudden, her response came instantly, like an echo. When it comes to threat assessment, Coppelia’s judgment is trustworthy. Though that first answer was clearly her own biased joke.

More importantly, the boy held by the neck isn’t reacting at all, even with Dan gripping him. I can’t tell if Dan doesn’t realize how much force he’s using because of the lack of reaction, or if he’s too desperate to notice anything. Either way, it looks like he’s squeezing far too hard. A dangerous sign.

In the next instant, the words “danger,” “demon,” and “self-destruct” connected in my mind. I heard the metaphorical click as they snapped into place, and a blaring alarm went off inside me.

“Oh no, Dan! Let go of him immediately! If you don’t, a ‘Resonant Collapse’ will detonate and take out the entire area!”

“What nonsense are you spouting now…? Some desperate last-minute bluffing?”

Tch—! According to what we heard yesterday, even that slave trading company had only handled demonkind a handful of times. If that’s the case, then it’s no surprise Dan doesn’t know this. Even I wouldn’t have realized it if Coppelia hadn’t mentioned ‘self-destruct’—it reminded me of something I once learned from Regina about demonkind.

With the demon boy’s life hanging by a thread, I swallowed my frustration and began sharing the knowledge I had with Dan.

“‘Resonant Collapse’ is a trump card used by demonkind. It vibrates the surrounding mana—including what’s inside living bodies—at extreme speeds, destroying everything from within and without. Its effective radius is approximately thirty mertes. Because it engulfs the user as well, it’s effectively a suicide attack. But what makes it truly terrifying is that it affects anything containing mana. In other words, you can’t defend against it with magic or sorcery that relies on mana.”

Put simply, it’s like a magical version of a microwave. Unless you’re in a completely sealed space, there’s no escape—mana is present in the air, in water, everywhere. The only real countermeasure is to flee beyond its effective range.

This is one of the reasons demonkind has long been feared and reviled. Though more than a century has passed since the Divine-Demonic Holy War, Finis Jihad, and demonkind now has recognition as an independent nation, that knowledge and those records no longer survive in the minds of the general populace.

Given all that, I thought I had done a decent job explaining it in a way that even a layperson could understand, breaking it down clearly and simply—but…

“Too wordy. No amateur’s going to follow that explanation,” Cestlavie said with a sour look, dismissing my efforts.

And sure enough, both Dan and Martha looked completely lost. Their faces were full of suspicion and disbelief as they glanced between me and the demon boy, who was barely breathing.

“Hmph. If they can’t grasp Lady Clara’s kind and detailed explanation, the world would be better off without such dimwits,” said Coppelia, puffing out her chest even as I held her pinned.

“…You seem oddly relaxed for someone in your position.”

“Ah, I’m fully internally shielded, so Resonant Collapse doesn’t affect me. That’s just how I’m built, Lady Clara,” Coppelia answered smoothly.

Apparently, she alone would be safe in the blast zone—how very like this worthless maid.

Well, not that I’m helpless either. I can use spatial magic, so I do have a countermeasure: I could isolate the enemy into subspace at the moment of detonation. But there’s no need to reveal that card just yet.

Now then, in response to my desperate persuasion—though I had half expected it—

“This brat’s gonna use that? Hah, you’ve dug your own grave. His magic is completely sealed by this custom-made stigma collar. There’s no way he could self-destruct.”

Though he seemed a little shaken for a moment, Dan quickly regained his composure and sneered with arrogant confidence.

“That’s not all! While demons can trigger it deliberately, they also instinctively initiate Resonant Collapse at the moment of death if they are in extreme pain. Slave collars can suppress magic that influences the outside world, or mana that’s consciously manipulated—but they cannot stop this. You don’t have to trust my words, but at the very least, loosen your grip!”

To my near-pleading appeal, the only response I received was a sharp click of the tongue and a cold, unyielding expression.

“Forget it. I can’t trust anyone from your cult. And besides, I’ve been working for Cervantes Trading for over ten years, and I’ve never heard of any demon doing something like that when they die.”

“They say ‘Ignorance is a sin,’ and wow… it really is, huh?”