The Demon King's Desperate Gamble
A few hours before Kang Minwoo regained consciousness atop the Demon King's Castle tower.
"Your Majesty, preparations for the humans' hero summoning ritual are complete. The ceremony will begin shortly."
"...Very well."
The 17th Demon King, Ernate, who had only recently broken her seal, sat alone and forlornly upon her throne. At her feet, beneath the dais, knelt a girl in a maid outfit. Unlike the Demon King, she appeared at first glance to be an ordinary person—but her skin was so pale it seemed translucent, her eyes a deep crimson, and her unusually sharp fangs betrayed that she was something other than human.
The Demon King, Ernate, spoke.
"And preparations on our end? No issues?"
"Yes, for now... But, Your Majesty... are you truly sure about this?"
The girl's clear voice carried deep concern.
"It doesn't matter. It's far too late to turn back now."
"But—"
"The ritual proceeds. No takebacks."
"...Representative of the vampire clan, Siola. I obey Your Majesty's command."
With those words of submission, the vampire girl who called herself Siola transformed into dozens of bats and vanished.
Once Siola was gone, the vast main hall of the Demon King's Castle held only the Demon King, Ernate, alone. She let out a sigh—how many was this now?
"Really... have I done the right thing?"
She had put on a resolute front for Siola just moments ago, but it was undeniable that she herself was riddled with anxiety. No more defeats could be tolerated. This was the greatest gamble in the history not just of her reign, but of all Demon Kings before her. If it failed, she might be completely annihilated by the humans before she even had a chance to reseal herself.
Though unavoidable for the sake of the plan... was it because of her premature revival, leaving her without her full power? Ernate, whose name was synonymous with terror, had grown uncharacteristically weak-willed. Recalling the memories of past Demon Kings who had always faced humans with overwhelming dominance, she tried to steady her nerves. But the anxiety lingered, and unconsciously, her fingertips caressed the large orb—her core—at her chest.
"Perhaps... it's this body."
Ernate glanced down at her own form, specifically the voluptuous swell of her breasts, then clicked her tongue in irritation.
Thanks to her early revival, Ernate had awakened before the humans' hero summoning—but at no small cost. The 17th Demon King, Ernate, was the first to incarnate as a female. It was proof that she hadn't yet regained her true power. The Demon King's trait of inheriting all memories of predecessors made this female body feel utterly alien to one who had always lived as male. Perhaps her un-Demon-King-like anxiety stemmed from this body, she thought for a fleeting moment.
But Ernate quickly banished the notion.
"It doesn't... matter. As long as I can bring defeat to the humans... as long as I can plunge that loathsome hero and his companions into utter despair. The gender of this flesh is trivial."
Muttering to herself, the Demon King, Ernate slowly surveyed the hall with a somehow lonely expression. Had she fully revived, this vast space would be filled with her loyal subordinates. But now, her only truly intelligent follower was that vampire girl, Siola. Of course, Siola was one of the Demon King's most elite and devoted vassals—but having just one such officer made the Demon Army look rather shabby.
Yet if the plan succeeded, Ernate would gain another subordinate. And that new minion, summoned from the same world as the hero, would surely bring her victory in the war against the humans.
The Demon King, Ernate believed it without doubt.
...
The last descendant of the vampire clan, Siola, was a faithful vassal who had served the Demon Kings generation after generation, one of the Demon Army's top elite officers. Before the previous Demon King was sealed, he had entrusted her with part of the "Anti-Hero Summoning Plan."
The final battle between the previous Demon King and hero ended in the hero's victory. The hero's party, alongside the imperial forces, began purging the Demon Army remnants—but Siola managed to escape the humans. In the process, her entire clan fell to the hero's blade.
Siola had endured even that sacrifice to survive alone for a special reason. She had a mission directly from the Demon King: steal the humans' hero summoning ritual formula.
Siola infiltrated the castle undetected by the imperial forces focused on the final battle. A prodigy even among vampires renowned for stealth, she successfully stole the formula. However, its structure forced the next Demon King, Ernate, to revive ahead of schedule. They couldn't perform the summoning without syncing to the humans' dimensional gate timing.
The Demon King, Ernate prepared their own summoning ritual in tandem with the humans' gate opening. It mirrored the humans' basic ritual—but with one key difference. When summoning a hero, humans guided the ritual to draw someone fitting the hero's qualities: valor, wisdom, compassion, justice. The formula was designed for one possessing all four.
Using it unchanged would just summon another hero, so the Demon King tweaked it to call someone they needed: wicked and cruel, harboring deep hatred for heroes.
Siola finalized all preparations and received Ernate's final confirmation just before activation. Now, they just needed to sync with the humans' timing.
"-- --- --!"
As Siola chanted, the massive magic circle at her feet blazed with radiant light. For an inter-dimensional summoning, the incantation was long and intricate. Sweat poured from her as in battle with humans; she poured everything into constructing the ritual. For her king, and for her clan's vengeance, Siola gave her all.
As time passed, the circle's glow intensified, soon enveloping the entire underground cavern. At last, the ritual ended.
"Hah... hah... Did it... work..?"
Exhausted from performing the massive ritual alone—what normally required all the empire's court mages—Siola collapsed to the floor. Without Ernate's mana support via the core, even a skilled mage like her couldn't have done it solo.
Soon, the blinding light faded, and the magic circle powered down completely. Siola peered at its center.
It was empty.
"Nothing...? That can't be... There was definitely a reaction..!"
After such sacrifices... failure was unthinkable.
"How did it go, Siola?"
"Y-Your Majesty..."
Demon King, Ernate had appeared before her, gazing at the empty circle. Siola hastily corrected her disheveled posture and bowed her head.
"F-Forgive me, Your Majesty! It's my failure...! Kill me!"
"..."
Ernate silently looked down at the prostrate Siola.
Failure? No, it hadn't failed. Ernate had watched the ritual too. Siola hadn't erred.
Then—
Rumble...
A faint tremor shook the ground—not an earthquake, but an impact's echo.
Ernate murmured.
"As expected... I see."
Such a massive inter-dimensional ritual offered no guarantee of pinpoint accuracy. The position had merely shifted; the summoning had succeeded.
"Stay here. I'll return shortly."
"Y-Yes."
As Ernate vanished, Siola gathered her weary body. Though ordered to wait, the future was uncertain. To assist her king, she needed to recover quickly.
"Your Majesty... please be safe."
The Demon King had no equal on the continent save the hero—but now, in her incomplete revival, she lacked full power. And since the summon was from the hero's world, complacency was fatal. They had to prepare if the summon refused allegiance.
A high-risk gamble, but with no retreat. For vengeance against the humans, Siola reaffirmed her resolve: she would do anything.