The fallen Demon King's flesh was already beginning to decay.
It was due to losing the horn that served as his catalyst.
He had lost the stake that kept him anchored to the world, and was trying to return to being a corpse.
Upon sensing the change within himself, the Demon King gave a self-mocking laugh.
"Once again... I... am defeated, am I not... How shameful..."
I halted my steps at a certain distance from him.
Then, I posed a question towards him.
"If you had managed to kill me, what did you intend to do in the world beyond that?"
"...The restoration of demonkind. It was the same ten years ago... We have been oppressed. The humans, who reign as the dominant species, bring calamity. Therefore, I had to... eliminate them."
"A species that brings calamity, you say?"
I murmured those words, turning them over in my mind.
The Demon King's assertion was not wrong.
The current me was born from the culmination of humanity's choices.
I had no intention of pushing responsibility onto them, but they were undeniably a factor.
"Foolish humans... history has proven it... I intended to wipe the slate of human history clean, and thereafter, inscribe the history of demonkind..."
The Demon King revealed his true intentions.
I never knew he harbored such thoughts.
In life, we had fought without him ever being able to speak this openly.
The Demon King fixed his hollow gaze upon me.
His mouth, dripping with blood, continued to form words.
"O current Demon King... kill me. That is the victor's privilege... step over my corpse."
"...Understood."
I nod and raise my sword.
This memento sword is a fatal weakness to the Demon King.
The previous Demon King, the current Hero, and the Holy Maiden.
They share something in common.
All of them met their end by this very sword.
The Demon King, who contains the essence of all three, is vulnerable to attacks from this sword.
One might call it a conceptual weakness.
Even if wounded, he cannot regenerate easily, and destruction of the brain or heart leads to death.
No amount of life force matters.
Without a catalyst, the Demon King would eventually perish on his own.
However, there is no telling what he might do in that time.
It would be best to end him here.
"The world you are weaving, is it..."
The Demon King murmurs deliriously.
His gaze is fixed upon the sky.
My image is not reflected there.
"What is this, all of a sudden?"
"No... I find myself wanting to see what that future holds... how foolish, to still harbor regrets at this stage. It is truly pathetic..."
The Demon King gave a troubled smile.
This was a far weaker sight than her usual self.
Perhaps facing death had brought her clarity.
(This must have been her true nature all along)
A Demon King cannot afford to show weakness.
Even her true feelings had to be buried deep, sometimes forcing her to act ruthlessly.
It is something I am acutely aware of every day.
"Sage Dwight, was it... From the depths of the underworld, I am cheering you on... perhaps..."
With those words, the Demon King closed her eyes.
Her expression was peaceful.
"—Former ruler. Rest in peace."
I said quietly, then brought my sword straight down.
The blade pierced her heart, and her entire body hardened like ceramic.
Then, it began to crumble from the edges.
All that remained was a mound of ash.
There was no trace of the Demon King left.
The pile of ash was swept away and scattered by the wind blowing through.
I withdrew my sword from it.
At that moment, a faint groan reached my ears from some distance away.
I turned toward the sound.
"Graaaah...gah...grrk..."
There, Balk was groaning in strange cries as he tried to stand up.
Blood-soaked, he was breathing heavily.
(He was alive?)
I had assumed he was dead, but it seemed he had somehow endured. The wound from the Demon Lord's spear was repaired and the bleeding had stopped. It appeared he possessed some kind of regenerative ability.
I approached, my sword in hand.
"Guuh...!"
Balk looked at me with a terrible expression.
He hurriedly fumbled inside his clothes and pulled out a small glass vial. It was filled with a purple liquid.
(Is that a beast potion...?)
I surmised the vial's contents. The cornered Balk apparently intended to use his last secret weapon. He was a tenacious man to the very end. Even after the Demon Lord was defeated, he still seemed unwilling to give up on killing me.
Balk opened the vial's seal without hesitation and gulped down the contents. He swallowed with a grimace, threw the empty vial aside, and glared at me.
"DWIGHT!"
Balk’s screaming voice dropped into a low, distorted growl.
The slender body began to swell, the skin shifting to a sickly green.
Clothes that no longer fit burst apart.
Wings sprouted from his back, and a tail was also visible protruding from his rear.
"UGOOAAAAA!"
Horns broke through the skin of his skull.
His mouth gaped wide, lined with rows upon rows of sharp fangs.
The rapidly accumulating magic power was on a scale incomparable to moments before.
Balk, who had been human, transformed in the blink of an eye.
He now stood in a form difficult to identify as either demon or magical beast.
"You alone! I won't forgive you alone!"
Balk compressed magic power into both arms.
Ready in both fists, he struck with killing intent.
I swung my heirloom sword in an arc, severing both of Balk's fists.
*Thud.* The fists fell to the ground.
"GUOOOOUUUU!?"
Balk screamed, blood spraying from the stumps.
Seeing his upper body reel back, I slashed at his knees.
With a reversed blade, I tore through his thigh and flank.
Tendons severed, Balk collapsed to his knees.
Even so, he wouldn't give up, lunging forward with his mouth agape to bite.
I shattered both of Balk's eyes with a flash of my sword.
Ignoring his agonized writhing, I unleashed a continuous barrage of strikes.
There was no mercy here.
Thoroughly strip away any capacity to resist.
"Gyii, Guu..."
The now helpless Balk groaned in pain.
His arms hung limply, barely functional.
His wings and tail were half-severed.
Muddy blood flowed from his entire body, marring the ground.
(It's over.)
The monster drug was, in the end, nothing more than a futile struggle.
He had just been a nuisance; there was no sign he had hidden any further tricks.
Just as I was about to cut him down, Balk screamed.
"W-wait! Let's, negotiate!"
"..."
I stopped my sword.
Speaking with a strange pronunciation, the monster-like Balk forced a smile onto its face.
"If it's me, I can revive the Hero! Even the Demon Lord made me help bring him back, so you can trust me...!"
Rushed out, it was a plea for its life.
It's a cliché, but a valid approach.
He was trying to survive this situation by piquing my interest with the word "hero."
(Indeed, not a bad method, but...)
I stared at Balk, expressionless.
He gulped, then raised his voice further.
"Ahh, Dwight! Don't you want to meet the hero once more! I know it! You do want to meet them! Thus, here is the prudent choice—"
"I refuse."
I swung my heirloom sword.
Balk's head separated from his torso and danced through the air.
After spinning, it hit the ground.
The torso gushed a fountain of red, then collapsed as the magic it contained dispersed into mist.
I stepped back to avoid the splatter and lowered my sword.
There were no hostile presences around.
I flicked the blood from the blade and sheathed it gently.
—Thus, I brought a final end to the series of disturbances.