Prologue
Demon Lord Erinyes.
That was the name of the one who once ruled the southern continent.
Possessing a beauty that could drive all to madness, no one could resist the enchanting voice that flowed from their lips.
Known also as the Fallen Sovereign, a grand archangel who had plummeted from the heavens.
It is said that a thousand years ago, they were defeated in battle by the Hero Abel and have since slumbered within the sealed prison beneath the Final Labyrinth.
Such tales are known to every soul on the southern continent.
I—Eugene Santafield—had heard them countless times since I was a child.
Demon Lord Erinyes was supposed to be a figure from picture books, a legend from a distant world... or so I thought.
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“Um… Headmaster Uther, are you truly planning to take this student to the ‘Forbidden’… the Seventh Sealed Prison? No matter how you look at it, isn’t that far too dangerous?”
The one asking with a worried tone was a young teacher from Lykeion Magic Academy.
Due to certain circumstances, I had left my hometown and enrolled in Lykeion Magic Academy, located in the labyrinth city at the heart of the southern continent. On my very first day, I was summoned by a teacher.
“There’s no need for concern. If anything happens, I’ll take full responsibility,” the headmaster replied.
“If the headmaster says so, I won’t press further, but…”
An unsettling conversation unfolded before my eyes.
“Uh… where exactly am I being taken?” I asked.
“You’ll understand once we get there. Eugene-kun, just follow us,” the headmaster said.
“Uh… alright…”
Led by the headmaster and the young teacher, I arrived at a massive black gate behind the academy.
Zuzuzu… A sinister magical energy seeped from the enormous gate.
Could this be the miasma, the so-called corrupted magic?
“E-excuse me… Headmaster, I can’t go any further!”
Before I realized it, the teacher who had been walking with the headmaster had stopped, lingering behind.
With a small sigh, the headmaster turned a curious gaze toward me.
“Eugene-kun, are you feeling alright?”
“Huh?”
I tilted my head at the question, glancing around and then down at myself. Nothing seemed out of the ordinary. I couldn’t understand what the headmaster was worried about.
“Heh heh… just as I suspected,” the headmaster chuckled. “You’re the only student to ever pass the white magic specialization test I made as a joke long ago. I had a feeling you’d be able to enter the Seventh Sealed Prison.”
The headmaster beamed with delight, though I wasn’t sure why they were so pleased. But something else weighed on my mind—what lay beyond this ominous black gate?
In the labyrinth city, there was a certain legend: a thousand years ago, this was the site of the final battle between the legendary hero and the Demon Lord.
And it was said that even now, the Demon Lord remained sealed within.
“Headmaster, beyond this…”
Just as I started to ask—
…Gogogogo… Gogogogogogo… Gogo…
The ground trembled. It was another earthquake, one of many that had been occurring since yesterday.
“Eek…! It’s the Demon Lord again…!”
The teacher behind us yelped, tumbling to the ground. The headmaster glanced back with a troubled expression.
(…Demon Lord?)
The teacher’s words piqued my curiosity, and I looked at the headmaster.
They met my gaze directly.
“Now then, Eugene-kun, there’s something I must tell you,” the headmaster said.
“Y-yes?”
Though slightly intimidated by the aura of magic and authority radiating from the headmaster, I nodded.
“Beyond this gate lies the Demon Lord, still under seal.”
“…!”
I swallowed hard. Hearing it stated so plainly made my body stiffen with tension.
The concept of a “Demon Lord” wasn’t unfamiliar on the southern continent.
Rumors persisted that a Demon Lord still reigned over the distant northern continent, but on the southern continent, the last time one held dominion was a thousand years ago.
For the past millennium, there had been no record of a Demon Lord appearing here.
“The earthquakes since yesterday are a sign that the Demon Lord has awakened from their seal,” the headmaster continued.
“…Awakened!?”
The words slipped out louder than I intended.
“That’s why we need to investigate. However… I’ve long been despised by the Demon Lord. It’s only natural, since I’m the one maintaining the seal. If they saw my face, I might not survive the encounter.”
“…So what am I supposed to do?”
Lykeion Magic Academy was the southern continent’s premier institution, and its headmaster, Uther, was renowned as the greatest mage on the continent.
If even they couldn’t face this Demon Lord, what could a mere student like me possibly do?
“Demon Lord Erinyes is usually a mild-tempered being. They’re unlikely to attack a boy like you out of the blue… probably. I’d like you to check on them in my stead. Of course, I’ve prepared a gift to appease their mood. At the very least, you could toss it in front of their cell and leave.”
“It doesn’t have to be me, does it…? I mean, why me, a new student?”
It was a reasonable question. Surely there were others more suited to the task.
The headmaster’s expression grew solemn as they responded.
“That man cowering back there is the academy’s foremost expert in barrier magic.”
“…Huh?”
I blinked, turning to look at the teacher.
“Don’t be ridiculous!” the teacher shouted. “I could’ve gone in a few years ago! But then you started summoning mythical creatures from all over the world, Headmaster! Now the Seventh Sealed Prison is a chaotic mess no one can enter!”
The headmaster’s face twisted into a sheepish grimace.
“Well, I couldn’t help it—it sounded fun,”
I’d imagined the headmaster as a stern, dignified figure, but maybe he was more carefree than I’d thought.
“Now, Eugene-kun, my request is as I’ve explained,” the headmaster continued. “And it won’t be for nothing. If you deliver this gift to the Demon Lord, I’ll waive your tuition for an entire year!”
“Tuition waived!?”
That was tempting. Originally, I’d planned to work after graduating from my local school, following in my father’s footsteps at his workplace. But due to a personal issue, that fell through.
My father forgave me easily—or rather, he kicked me out, saying, “If you’re just going to laze around the house, go abroad and broaden your horizons!”
He’d paid my tuition, but I’d felt guilty about it, wanting to stand on my own. If I could cover my own fees, it’d be a way to save face with him.
“…Alright. I’ll take the mission.”
“Are you serious!? Eugene-kun, you should reconsider—”
“Besides, I can’t pass up the chance to see a legendary Demon Lord with my own eyes.”
Half of that was bravado, half genuine curiosity. It’d make a great story to tell my father.
“Well said! As expected of the Sword Saint’s descendant!”
The headmaster grinned broadly. The “Sword Saint’s descendant” bit was something my father had scribbled on my application.
The Sword Saint was a legendary figure who brought temporary peace to the eastern continent five hundred years ago. Supposedly, our family lineage traced back to them—technically true, but unverifiable and dubious at best.
“Then let’s be off.”
The headmaster muttered a strange incantation I couldn’t quite catch, and the black gate creaked open slightly. He slipped inside, and I followed.
…Zushin. The gate slammed shut behind us.
I peered into the pitch-black prison. Magical lamps cast faint light around us.
The headmaster pressed deeper inside, and I trailed a little behind. The air was stagnant, hard to breathe. I layered every barrier spell I knew over myself.
…Zuzu… Zuzu… Zuzu…
…Teke… Riri… Teke… Riri…
Shan… Shan… Shan… Shan…
…Kyakya!
…Kusukusu… Kusukusu… Kusukusu…
The underground prison was dim. Dragging sounds and eerie wails echoed from all directions.
Some noises almost sounded human—or maybe not.
“…Hey, you. Want to play over here?”
A whisper brushed my ear. I whipped around, but no one was there.
“Eugene-kun, that’s the voice of a malevolent spirit. Pay it no mind,” the headmaster warned.
“Y-yes.”
Heart pounding, I steadied myself and followed the headmaster deeper.
After a while, we reached the innermost chamber.
The air grew heavy. Despite the lack of heat, sweat wouldn’t stop pouring from me.
My instincts screamed that going further was dangerous.
“I can’t proceed any farther. The Demon Lord would sense me,” the headmaster said. “Eugene-kun, take this.”
With a pop, they conjured a basket from thin air and handed it to me.
Inside was bread, a bottle of wine, and a single red fruit.
“This is the gift for the Demon Lord?”
It seemed awfully simple. Would this really appease them?
“They’ve been asleep for over a century, so they’ll be famished upon waking. Food should do the trick. The fruit is a rare delicacy called the ‘Fruit of Life.’ It was a hassle to acquire, but oh well.”
“The Fruit of Life!?”
A legendary fruit said to grant eternal youth. This was it…?
As I stood there, stunned, the headmaster gave me a gentle push on the shoulder.
“I’m counting on you. Good luck, Eugene-kun.”
“Understood… Headmaster Uther.”
Urged forward, I ventured alone toward the deepest part of the prison. My footsteps echoed unnaturally loud. Soon, I stood before a cell far larger than any other in the underground.
Now what? Should I just leave the gift here? Or maybe call out to them…? As I hesitated—
“…Who’s there?”
That beautiful voice sent a chill through me, as if ice water had been poured over my head.
Slowly, I turned toward the sound.
“A new face, aren’t you, boy?”
Eyes as crimson as blood stared back at me.
Skin as white as snow and long hair shimmering like stars.
And upon her back, vast wings of deepest black.
A form exactly as the legends described—yet a beauty surpassing even those tales.
“What is your name?”
“Eugene… Santafield…”
“Ah, a fine and valiant name. Come closer.”
Fear rooted me in place. My legs trembled faintly.
Yet, drawn by an irresistible allure, I found myself stepping slowly into the cell, guided as if by fate.
This encounter—unbeknownst to me—would soon spark a tumult that engulfed the entire continent, setting me on the path to becoming the “Sword Saint.”