Reincarnation as a Great Demon Lord - Chapter 8

Chapter 8: The Great Demon Lord... in a Mixed Bath!?

According to the female knight Eagret, after the previous Demon King was killed in battle, the Red Scale King (Sekirin-ou) retreated deep into Blue Flame Mountain (Souen-zan).

His goal was to heal his wounds and gather strength for the next war against humankind.

That, in itself, wasn't strange. But about a year after he vanished... a colossal red dragon appeared.

It took up residence within the volcano's crater, absorbing the surrounding magical energy and drastically warping the environment. It activated the volcano, covered the sky in ash, and caused rain to turn gray with soot.

Naturally, the Dragonfolk warriors attempted to eliminate the giant dragon, but they all failed miserably. Even Eagret, the village's mightiest fighter aside from the Red Scale King himself, couldn't leave a single scratch on it.

And during that desperate battle, Eagret noticed it:

A glow within the dragon's chest. The light came from the sacred treasure her father once guarded, the Radiant Heart (Kaku-yaku no Shinzou). The overwhelming aura pouring from the creature... was unmistakably her father's.

No one knew why or how it happened.

But one thing was certain—unless something was done about the Red Scale King, both the village and the Dragonfolk would perish.

And thus, it fell to me—the Great Demon Lord—to defeat the dragon that dwelled within the volcano's crater.

...Except, since the dragon was actually the very general I’d been seeking, I couldn't simply slay him. I had to find a way to restore him to his original form, and also retrieve the Radiant Heart embedded in his chest without destroying either.

A near-impossible task. I hadn't the faintest clue how to pull it off.

There was nothing like this in the original game, so there was no precedent to draw from. Which meant it was time to think differently.

So, I decided to take a bath.

“...Haaah.”

Soaking up to my shoulders in the hot spring behind the Dragonfolk village, I exhaled deeply.

No matter what world I lived in, my soul was still fundamentally Japanese. The warmth of a bath and the comfort of hot water soaking into one’s bones were deeply ingrained.

It was an open-air bath. If only there'd been a full moon overhead, it would've been perfect, but I wasn't one to demand luxury.

Apparently, most of the springs had been destroyed when the dragon appeared, but this one had miraculously survived. I'd planned to bathe only after completing my mission, but Eagret had insisted so earnestly that I couldn't refuse.

Besides, a bath was excellent for thinking. My blood flowed better, my thoughts grew clearer, and for once, I was completely alone here.

A Final Boss rarely gets this much complete private time.

As I soaked, I suddenly remembered the tool bag that Arcelia had given me—and, more importantly, the communication device inside.

Arcelia is the greatest technician in this world. If I shared the situation with her, she might think of a solution. A true ruler doesn't lean on others lightly, but knowing when to rely on them is also part of leadership.

I retrieved the device. It resembled an old-fashioned transceiver, powered by magic. The moment I gripped it, it flickered to life.

“Ah—hello?”

“—I hear you. Connection’s stable. Volcanic ash interference: minimal.”

It connected instantly. No ring, no delay. Which meant... she'd been holding onto her own communicator all this time.

Heh. She’d acted like it was 'just a field test,' but now it seemed rather endearing.

“It is I.”

“I know that. Hold on, I’ll enable the visual feed now.”

“Wait—don’t—”

Too late. A holographic projection shimmered above the device, and there she was—Arcelia, sitting at her desk, rubbing sleepy eyes behind her glasses.

...Seen like this, she really did look like an ordinary little girl. A "child prodigy scientist," as one might say. Adorable, really.

Unfortunately, I happened to be completely naked in front of her. Thank the heavens for the steam and the bathwater at least covering the essentials.

Wait—this thing had video call functionality!?

“...Why are you naked?” Arcelia asked, maintaining her composure.

Thank goodness. If she’d reacted like an actual child, I might've been branded a criminal. Even if it was an accident and not my fault, that's the sort of stain that would mar my noble Final Boss reputation.

“I’m in the bath. You should try it sometime—it’s quite relaxing.”

“The fact you have time for a bath means the village situation is better than expected. But since you're calling, I assume there’s a problem?”

“As expected of you. I require your knowledge and wisdom.”

I explained everything that had happened. Arcelia listened in silence—always a sign she was thinking deeply and was interested in the case.

“...A 'Reversion to Ancestry,' perhaps,” Arcelia said when I finished describing the Red Scale King's transformation.

As expected of my resident mad scientist. Despite her childish form, her insight and knowledge are first-rate.

“What is that?”

“You remember what Selen told you—how the Demon Race evolved from monsters?”

“I do. The more intelligent beasts eventually became demons, correct?”

“Exactly. But rarely, the reverse happens. They lose their intelligence, their humanoid form—and revert. They gain immense magical power, but most die soon after.”

That makes sense. It matches the Red Scale King’s case almost perfectly.

The Dragonfolk descended from dragons. A reversion would mean returning to that form—becoming a dragon once more.

Perhaps even some of the "monsters" fought in the original game had once been demons who’d suffered such a fate.

“Still, no documented case shows a transformation that massive. The Heart of Radiance is likely influencing the process.”

“So if we remove the Heart of Radiance... could we restore him?”

“That depends on what you call ‘restore.’ The most likely result is that the dragon dies the moment the gem is removed.”

“...Any other possibilities?”

“Can’t say without seeing it myself.”

“Then come join us. To save the Dragonfolk, your expertise is indispensable.”

“...Understood.”

She blinked, surprised, then sighed softly—not in exasperation, but admiration.

No doubt she was impressed by my unshakable sense of responsibility as a ruler. A true Final Boss never breaks his word. I had told Eagret I'd save her village and her father—and I meant to deliver.

“But it’ll take time. Two days, at least.”

“That’s fine. I’ll contact you if the situation changes.”

The stalemate wouldn't shift in two days. No issue there.

I cut the transmission and leaned back into the water, exhaling slowly. Sleep tugged at me, so I splashed my face to stay awake.

We still lacked a concrete plan, but identifying the cause was massive progress. As with any illness, you cannot achieve a radical cure without grasping the source.

Before Arcelia arrived, I’d need to draft some sort of strategy—survey the terrain with Eagret tomorrow, map the path to the crater, and identify possible allies or resources nearby.

Information is power, even in a world of swords and sorcery.

In my previous life, my information network had exposed election fraud and secured me crucial allies. Had I lived longer, I might have ruled Japan itself.

Ah, such a waste.

But I don't despair. That's not the way of a Final Boss. Every setback is merely the foundation for my rise.

Even in bleak times, there's always a spark of hope—and for me, that's enough.

“Y–Your Majesty…”

A shaky voice called from the dressing room.

Eagret. What could she want at this hour? Had something happened?

“Eagret. What is it? Has something urgent occurred?”

“N–No, not exactly, but... um, that is...”

“What is it? I cannot hear you from there. Please speak up a little.”

“R–Right. Well, it's just that... here... um...”

She was stammering badly. That wasn’t like her at all. Had something truly gone wrong?

Sighing, I decided to step out. I hadn't soaked nearly long enough, but duty came first—

“E–Excuse me!”

—and then Eagret burst into the bathing area, wearing nothing but a single towel.

“Wha—!?”

An undignified yelp escaped me—most unbecoming of a Demon Lord. I scrambled back into the water, but our eyes had already met.

W–Why!? Why was she here!? Why only a towel!?

It wasn't hiding anything! She was blushing furiously, face turned away, but still—what was she thinking!? Was this normal for the Demon Realm!?

No—stay calm, me. Final Boss Cool Mind. A true ruler does not panic, fluster, or falter.

...Alright. Calm restored. That took, what, a second? Impressive, if I do say so myself.

Now then. Time to handle this like a gentleman.

“Eagret, what’s the meaning of—”

“—I–I, Eagret Eurytheia, humbly beg for your favor (onjō), my lord! I–I am unworthy, but... p–please, accept me!”

...And just like that, my Cool Mind shattered into pieces.

If my interpretation was correct—and I prayed it wasn't—then by “favor,” she meant the R-rated kind.

..................Why. Just... why!?

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