"Hold this line at all costs! Do not let them break through!"
One soldier—the captain tasked with this position—screams.
A spear pierces his face.
It was the work of a skeleton that charged in a suicidal rush.
The individual that killed the captain is immediately cut down by other soldiers.
Still, the damage on our side is minor.
The achievement of destroying their command structure is significant.
Furthermore, if I send miasma, the broken skeletons will rise and once more throw themselves at the soldiers.
This is a city in the northern part of the Kingdom.
Currently, I am invading with one hundred and twenty subordinates.
Using my magic, I shattered the main gate, and while adding the soldiers who stand in our way to the ranks of the undead, I advance toward the lord's mansion.
"Shit, they just keep coming...!"
"If you have time to whine, shut up and fight—"
"Tch, those bastards are even using arrows!"
The soldiers are being forced into a hard fight.
They can do nothing against the arrows fired by the undead.
Even if they counter and take down a few, the effect is minimal.
To make matters worse, the front-line undead charge into them without a care for their own damage.
Among them were several ogres wielding large shields.
They were subordinates of Luciana's monsters.
This time, on a trial basis, we had them participate in the expedition.
The ogre advanced, heedless of the soldiers' attacks.
With its raw power, it swung down its club, shattering their formation in a single blow.
Then its roar induced a state of panic.
(Hm, not bad at all.)
The ogre integrated surprisingly well with the undead army.
Fighting together posed no problem.
In fact, they meshed beautifully.
The ogre would break the soldiers' lines, and the undead would pour into the gap.
Disregarding casualties, they widened the breach in the formation.
A magnificent wave attack.
The lord's manor was now within striking distance.
"Lowly humans. Kneel before the Undying King... NOW!"
Grom, commanding the army, raised his staff.
The precious stone set in its hilt glowed, unleashing a black fireball.
The fireball traced an arc over the soldiers' heads, then exploded directly upon the lord's manor.
A pitch-black inferno rose, and the manor began to burn fiercely.
The soldiers' attention was drawn to it, and in that moment, they were subjected to the undead and ogres' relentless pursuit.
Watching the entire scene, I called out to Grom.
"The objective this time is not annihilation. Don't overdo it."
When called out, Grom slunk toward me with a hunched back, moving furtively.
He whispered, somewhat theatrically.
"No, Demon Lord. This is a necessary measure. If you wish to compel obedience, intimidation should feel just slightly excessive."
Grom seemed unusually confident.
I'd thought he was drunk on slaughter and cautioned him, but it didn't appear he had lost sight of his purpose.
Perhaps he was making adjustments in his own way.
Returning to his position, Grom unleashed another black fireball.
"Fuha ha ha ha! I shall show you my abyssal power!"
"..."
His delighted demeanor gave me a faint headache.
I was genuinely worried he might have lost sight of his objective.
Grom seemed to enjoy playing the part of a villain.
It was good for people to fear him.
But in his case, the power he possessed was too great.
If he miscalibrated, he could annihilate the entire place.
That would be problematic this time.
I would have to keep an eye on him to ensure his actions didn't become too extreme.
After that, we scattered the soldiers and reached the lord's mansion.
In the blink of an eye, we secured the interior and found the ruler of this town—the lord.
"S-stay away! Filthy undead!"
The lord crawled across the floor, screaming.
His guard had already transformed into a ghoul.
Thus, no one remained to protect him.
"…You. Do not think you will die easily. I will make you fodder for my beasts in the depths of your agony."
Grom spoke, his voice carrying a terrible weight.
It seemed he could not tolerate the lord’s foul outbursts.
Filthy undead was, I thought, an apt and precise description of myself.
"I will handle this from here. Stand down."
"Yes!"
At my command, Grom quickly withdrew and knelt.
His obedience remained as ever.
"The undead that destroyed the Royal Capital…"
The lord murmured, stunned.
He was drenched in sweat, his face pallid to the extreme.
I wondered if he might collapse if left alone.
I looked down upon the powerless man.
"So, you are the lord."
"And if I am? What of it?"
"I will put an end to you."
I seized the lord by the neck and lifted him into the air.
I slammed him against the wall without hesitation.
"Ah, gu—gah…!?"
In an instant, the lord’s eyes rolled back, and he began thrashing wildly, limbs flailing.
White steam rose from his entire body as his skin discolored and began to melt.
Then, with a sickening tearing sound, it liquefied and sloughed off.
The rapidly decaying lord soon collapsed into nothing but bones, crumbling to the ground.
At my feet, a blackened liquid remained.
"...Now then."
I cracked my neck and looked toward the far side of the room.
There, frozen in terror, were the humans who had been too afraid to move.
The lord’s wife and children.
"If you do not wish to end up like that, submit to me. I will spare your lives."
"H-hi—eeeee…"
My warning only drew a more horrified shriek from the lord’s family.
It was doubtful they had even grasped my words, but pressing them further would likely backfire.
I had given them more than enough fear to chew on—surely they would not do anything foolish.
This local lord had attempted to seize the now-ownerless territory left vulnerable by our invasion.
He prioritized self-interest over any sense of cooperation.
He had no interest in the Demon King’s manifestation; all he cared about was keeping his own coffers lined.
That was not how humanity should carry itself moving forward.
So I made them a lesson.
"Move out."
I turned on my heel and gave the signal.
The undead army withdrew from the lord's manor as one.
We walked through the eerily silent, blood-stained streets.
"My my, as expected of the Demon Lord! A masterful display!"
Grom praised me while wiping my hand with a handkerchief.
I shook my head and replied.
"Save your flattery. More importantly, what's the situation?"
"Yes. The lords in various regions are successively declaring submission to the Demon Lord. The purges for the sake of making an example seem to be effective. At this rate, conquering the entire continent is no mere dream!"
"I see."
I was satisfied with Grom's report.
It had been roughly thirty days since the remnants of the Demon Lord's army led by Luciana had arrived.
I was systematically destroying the kingdom using teleportation magic.
This would make them recognize the threat of the Demon Lord, while simultaneously cultivating the natural ground for humanity to cooperate.
Lords like the current one, who acted selfishly in the shadows, were being eliminated one by one.
I did not want a situation where people pulled each other down.
Those who lacked cooperation were not just unnecessary—they were a blight.
Through such painstaking efforts, the lords within the country had shown their intent to submit to me.
A wise decision.
If they defy me, they know their territory will become a nest of undead.
I will not actively interfere with them and allow them to live as before.
Their submission is likely a momentary lie, with their true intentions lying elsewhere, but that is acceptable. It is only natural psychology to watch for an opportunity to rebel. Indeed, it would be ideal if they were coordinating with other lords behind the scenes.
I basically allow plots to overthrow me to play out.
With the common goal of subjugating the Demon Lord, humans ought to cooperate.
Currently, with the fallen Royal Capital as the center, the domestic territories that submitted have been designated as Demon Lord territories. In terms of the balance of power, it is quite extensive.
While the actual territory under my control is only the Royal Capital, I am not overly concerned. The fact that I have invaded almost the entire kingdom, even if only on the surface, is what matters.
Having achieved my objective in this city, I cast the teleportation spell.
I returned to the Royal Capital, bringing all of my subordinates with me.
Passing through where the main gate once stood, Luciana was standing there.
She hurried over with light steps.
"Oh, Demon Lord Sama. Good day. You've returned quite early."
"The matter was resolved more smoothly than anticipated. Having only excellent subordinates was a great help."
The performance of those ogres was worthy of praise.
While undead alone could have broken through, their speed of advance is in a different league entirely.
At my words, Luciana puffed out her chest with pride.
"Oh right, oh right! I worked so hard to train you! It's an honor to be of service."
Luciana narrowed her eyes and closed the distance with a sultry expression.
She traced my body with her hands while whispering softly.
"Hey, Demon Lord. How about some tea after this? Of course, just the two of us—"
"Your Excellency, you must not take this woman's offer! She is surely plotting something nefarious!"
Grom's ironclad interruption cut in.
This was already a familiar scene.
Since it was mostly harmless, I didn't bother stopping it.
Separated from me, Luciana pressed a finger to her lips in thought.
"Hmm... well, in a way, it could be called something nefarious."
"Do you hear that, Your Excellency! She has finally confessed! You obscene succubus, I shall personally deliver your final judgment...!"
"Quiet down. Save your bickering for later."
When I reprimanded them lightly, both turned toward me.
And retorted in unison with forceful tones.
"We're not bickering!"
"We are not bickering, Your Excellency!"
These two, despite everything, might actually get along quite well.
The way they mirrored each other forced that thought upon me.
Ignoring the pair sparking with tension, I began walking toward the castle.
Naturally, Grom and Luciana followed in my wake.
Seeing them cut off their argument so abruptly, they really did seem to get along.
In the end, the three of us proceeded down the street.
The sight within the fallen Royal Capital had undergone considerable changes.
Goblins ran along the roadsides, carrying building materials.
An orc received them and used tools to repair damaged buildings.
Across the way, kobolds were tilling a field created in an open lot.
They were working diligently with hoes.
Succubus flew through the air above.
They were gathering materials abandoned throughout the capital.
Humanoid giants made of rubble were clearing building debris one by one.
They must have been a golem summoned by someone.
The usable materials gathered by the goblins were then transported away.
They were the remnants of the Demon Lord's army, under Luciana's command.
Having been permitted to live in the castle town district, they had spontaneously begun urban development.
They spent their days laboring to enrich their lives even slightly.
Among them, there were a few humans as well.
Slaves who had been mixed in with the remnants.
They said such people were valued because they possessed specialized skills or were dexterous.
It was also said some among them could use magic; though awkward, they were hardy and adapting to the environment.
I observed these scenes with admiration.
"The city development is proceeding well."
"I've learned all the necessary cultivation techniques over these ten years. I had to, just to survive. Though the miasma here is dense, once that's dealt with, it's actually quite a bountiful land."
"Of course. It fell, yes, but it was the Royal Capital originally."
The miasma that permeated the city was concentrated within the castle.
This was because it was causing health problems for other monsters and humans.
High concentrations of miasma are toxic to living humans and monsters.
Currently, they could live without issue.
Incidentally, the large number of undead were stored beneath the castle or in the city's warehouses.
Their numbers had rapidly increased from expeditions to various regions, and the excess was made to wander the outskirts of the Royal Capital.
From the perspective of numbers alone, they were currently the greatest fighting force.
I intended to cherish them.
Once back at the castle, I looked down at the cityscape from the balcony.
It was still an unbelievable sight.
A region that had been contaminated, blanketed in miasma, was now beginning to function again as a center of life.
Moreover, humans and monsters were coexisting.
It was a scene I couldn't have even dreamed of in my former life.
It must be truly wonderful.
I desired true world peace.
This kind of tranquility, spun in this manner, was also welcome.
Even if it was just within a single city, I felt joy that its inhabitants were living together, regardless of race.
Ideally, this would be realized on a global scale, but that is exceedingly difficult.
Flaws would inevitably arise.
This system only functions because the Royal Capital is a limited space with few people.
(To create peace on a world scale, the optimal solution is indeed to place a great evil.)
That said, having accepted these residents, I do intend to protect them from coming external threats.
They are already citizens of my nation.
In return, I expect them to help stabilize the Demon Lord's Domain.
It is a perfect alignment of interests.
Just then, a sharp war cry pierced the air.
I turned my gaze toward the source of the sound.
It was a vacant lot on one corner of the city, where the knights' training grounds had been.
I could see monsters conducting group mock combat drills there.
They were holding these sessions voluntarily to prepare for battle.
A highly favorable trend.
(I must live up to their initiative...)
Through our successful invasions, we had seized over seventy percent of the Kingdom.
Total domination of their territory was now merely a matter of time.
From here, we would gradually extend the ravages of war.
In other words, we would invade foreign nations.
(How the various countries will move in response to the worsening situation—that is what matters most.)
Currently, there have been no announcements whatsoever.
It is likely due to the undead devastation being contained within the kingdom.
The situation is being observed for developments.
The ruling classes of neighboring kingdoms seem to be far more optimistic about the new Demon King than warranted.
That is why I have decided to act proactively.
I have no intention of confining the emergence of the new Demon King to a single kingdom's disaster.
I will engulf the entire world and thoroughly turn it upside down.
I will make sure no one can dismiss this as someone else's problem.
As the Undead King, I must demonstrate my true nature.