A demon who could see a certain future agonized.
Should this anomaly be eliminated, or left alone?
There were, of course, minimum countermeasures that could be taken against it. Yet regardless of whether he intervened or not, it was unclear whether it would be born at all.
The disadvantages of allowing its birth were undeniably immense. However, there also existed a clear long-term benefit: it would prune many of the budding warriors who could one day become threats to demonkind. Still, to avert one's eyes from the sacrifices of the demons in the present for the sake of that distant future—the price was simply too great. Worse still, as a result, the hero's party would reach the Demon King sooner, hastening the death of the Demon King he so deeply revered. That, above all else, was an unacceptable outcome.
Yet no matter which future he observed, one fact was already fixed: the Demon King would be defeated by the hero Himmel. If that was the case, it was also true that there were more urgent countermeasures to prepare than dealing with it. After all, he was but a single demon. Within the limits of time, the number of moves he could make was also limited.
To begin with, at the moment he first observed the possibility of its birth, whether it would come into existence at all was still uncertain. Even when he peered into a future where he deliberately dismantled the demon unit meant to attack that village, he could still see timelines in which it was born. Conversely, even if he allowed the attack to proceed, there were futures where it was never born. Regardless of whether he intervened or not.
Which worldline would ultimately be fixed—only time would tell.
And in the end, it was born.
Born into the world.
A hero who could also see a certain future agonized as well.
Because of the difference in the eras they lived through, by the time that hero observed it, it had already been born. And he came to realize that by leaving it alone, the sacrifices on humanity's side would be reduced.
As one who worried for humanity, its birth should have been celebrated.
But as a single human being—and above all, as the strongest hero—its existence was unbearably painful to behold.
Watching it run about without even realizing the truth was simply too much to bear. Even in timelines where it did become aware, what awaited was regret… or erosion. When he actually laid eyes upon its inner world, he could not count how many times he lamented whether a girl like this should be allowed to carry such a heavy, desolate world within her heart. Even though he himself no longer had the right to speak of such things.
More than anything, was it truly acceptable to entrust humanity's sacrifices to such a pitiable, wounded existence? Whether it realized it or not, was he not becoming a despicable being who selfishly forced that burden upon it? If he accepted that, could he still call himself a hero with pride, and trade his life with the demons alongside his comrades?
He should not accept it. He must never carve open its path. Closing that path would be far more merciful for it. And yet, if he did open it, countless people who should have died would be saved. Still, unlike himself, those who were saved would never recognize it as their savior. And as for himself, who would die anyway—there would likely be no reward for his deeds. That, at least, he did not mind.
But having decided to use it, was it arrogance to wish that it might at least be granted a proper salvation? If such a wish could never be fulfilled, then closing that path would be far more merciful.
No… no matter how he thought about it, wasn't it already too late?
""Honestly… this is truly beyond saving.""
The words of the two who would die together overlapped.
The great demon, unable to decide which future was best, chose a path that hastened his lord's death.
The Hero of the South, knowing this was the optimal choice, yet mocking himself for no longer deserving the title of hero.
Was this truly right? This was the best choice.
No—there was no way it could be right.
The tangled emotions of the two who crossed blades coincided completely—if only for this moment.
◇
It was probably what one would call a miracle that I was able to witness that existence.
I was about to participate as a volunteer soldier in the upcoming campaign by the kingdom's army to subjugate the Demon King's forces.
Adventuring is a free profession—but at the same time, an unstable one. With the wide variety of roles available, some adventuring parties can even gain more fame than ordinary officers. But such cases are exceedingly rare.
Many young adventurers dream instead of making a name for themselves as territorial soldiers under a count, or as guards protecting the royal court—seeking a more stable life. I was one of them as well.
Of course, the reality was that I had failed to achieve even those dreams, remaining an obscure adventurer.
Just before the subjugation mission, I was making the rounds of the town market to stock up on equipment and healing potions. As I was about to enter my usual weapons shop—the one that sold spears and swords—I spotted a strange figure exiting through its doorway.
Judging by her build and height, she was probably a girl, but because she wore a hood, I couldn't make out her overall appearance.
…And yet, when I caught a fleeting glimpse of her face through the gap in her hood, I found myself staring without realizing it.
A fleeting glimpse revealed fragile, pale pink hair.
Dark violet eyes that exuded a decadent aura, utterly unlike those of an innocent young girl.
Skin not yet fully mature—round and white, like fine porcelain.
Though her presence clearly belonged not to the light but to the shadows, there was also something about her that felt like untouched blank paper, an untainted purity with not a single mark upon it. In that moment, I realized that shadow and innocence could coexist, each respecting the other.
Once my gaze lingered on details like that, I could no longer deny it—even to myself.
To be perfectly honest, it was love at first sight.
Despite having seen only a fragment of her, I found myself watching until her back disappeared from view.
"Hah," I snapped back to my senses.
I reflected on how close I'd come to turning into a complete creep.
What was this feeling, when I hadn't even gotten a clear look at her face? Suppressing my racing heart, I turned my eyes back toward the weapons shop.
It was a shop I frequented often, yet I had never once seen a customer like her coming or going. And judging from what she carried, it didn't seem like she had bought anything.
Just what had that girl been doing in this shop?
—Maybe I should ask the shop owner.
Keeping my original goal of procuring weapons in mind, I entered the shop with that curiosity still gnawing at me.
"Welcome—… huh? Oh, it's you, kid."
The bearded shop owner greeted me with his usual lazy manner, barely looking motivated. I thought, as always, that he was an old man with no drive whatsoever—but since he somehow always gave me decent prices on equipment, I didn't actually dislike him.
"Same as always today, boss. Oh, and… there's something I wanted to ask."
"Huh? What is it, out of the blue?"
Steeling myself, I chose my words carefully as I asked him about the girl.
"Oh, that girl, huh. She said she didn't even have travel money, so at first I thought I'd kick her out. But then she started saying some nonsense about not coming here to buy anything…"
The shop owner trailed off, stroking his chin.
The young man desperately wanted to ask what on earth had happened between him and that girl, but he swallowed the urge and waited for the old man to continue.
After a while, perhaps deciding it was fine to talk, the shop owner took out a small parcel—just a little larger than his palm—from a drawer in the back and unwrapped it.
Inside was a black-lacquered tea utensil.
It was obvious at a glance that it wasn't the kind of thing that caught people's attention—there were no decorations of gold or silver, nothing flashy at all.
And yet, for some reason, the young man couldn't take his eyes off it.
"She said it was one of the treasures from a dungeon's vault. I appraised it with a magic tool—no doubt about it, it's the real deal. If she'd insisted on using this as currency, I wouldn't have known how to handle that… but it seems her real goal wasn't anything for sale in the shop. It was my collection in the back."
"...Your collection?"
"...Now that I've accepted this, I honestly had no intention of showing it to anyone but her—but, well, I suppose it's fine."
With a quick curl of his finger and a "Come on," he led the way deeper inside.
Past the corridor beside the wall lined with displayed weapons, and farther still, the young man followed the shop owner into a room.
…That room was far too oppressive to be called a mere "collection room."
A stone chamber that admitted no outside light. The walls, floor, and ceiling were completely bare—devoid of decoration, utterly lacking in playfulness.
The air felt like something forbidden was being sealed away there.
"…You've guessed right. These aren't so much a collection as they are things that should never be sold. They all look like they've got rarity and value, which makes them hard to get rid of—but I can't exactly sell them for money either, so this is where they end up."
"Honestly, I wish that girl had just taken them all off my hands," the shop owner muttered.
Seeing the many items stored there, the young man found himself agreeing.
He didn't know exactly what they were—but every single one of them radiated an aura that screamed trouble.
"The one giving me the most headaches is this."
Saying that, the shop owner brought over a single blade that had been hanging on the wall.
No—calling it a sword didn't feel quite right. It was closer to a katana.
Yet no matter how one looked at it, it didn't seem to be made of iron or any other common metal like an ordinary blade.
The texture was unmistakably that of hardened organic matter, and several protrusions lined the blade, growing out of it like something formed from bone.
—Wait. Bone?
No… that didn't matter right now.
What truly mattered was the black, malevolent aura emanating from the blade. Its shape aside, it possessed an ominous, disturbingly organic presence that hardly deserved to be called a sword.
"Um… this… extremely dangerous-looking sword is…?"
"…This is the Dark Dragon Bone Blade. When people talk about dark dragons, the Dark Dragon Horn is better known—mainly traded among mages as a catalyst for summoning magic.
This blade, though, is said to be made by carving the spine of a… dark dragon's juvenile."
"J-juvenile?!"
Hearing that, the young man froze. No matter how fearsome a dark dragon might be, this meant the blade had been crafted from the bones of a baby dragon.
He couldn't help but wonder if the blacksmith who made it had a few screws loose.
"The horns give off a similar evil aura, but as far as anyone knows, they don't actually carry a curse. This thing, though, is clearly cursed. Whether it's because of that or not, the blacksmith who forged it supposedly died in a mysterious fit of madness."
"…Then why on earth do you even have something like that?"
"I don't want to have it either. But it's not exactly something you can just hand over to anyone, is it? That's why I was hoping that girl would take it off my hands…"
After all, I did receive a fitting price for it, he added, glancing at the tea utensil in his hand.
…Right. He'd nearly forgotten, shaken as he was by the horrifying story surrounding the bone blade—but he'd come here in the first place because he was curious about that girl.
"And what does that girl do? She takes one look and leaves without even giving it a second glance. From her side, that's a raw deal, isn't it?"
From the shop owner's perspective, he'd merely shown her something incomprehensible, yet ended up receiving a valuable item in return. As both a person and a merchant, it must have sat poorly with him. And yet, the girl had left as if none of that mattered to her.
"I mean, I did say I'd show it to her if that's all she wanted—but who actually comes, takes one look, and leaves? Seriously…"
"But then why did she really leave after just one look? Wasn't what she was looking for there? Or did she get scared and run away after seeing things like this?"
The young man tilted his head at the strangeness of it—especially since she'd still paid the price before leaving.
"Who knows. But this is a merchant's intuition talking—somehow, the way she walked away… it felt like the back of someone who'd made a purchase. That's exactly why it bothers me. If she left without taking anything, then what on earth did she buy from me…?"
The shop owner sighed, muttering that he didn't understand it.
As the young man pondered alongside him, a thought suddenly surfaced and slipped out of his mouth.
"Or maybe it's not that she didn't find what she wanted, or that she got scared and ran away—maybe she really just needed to… see it. Just see it, and that was enough…"
"What are you talking about, kid? That makes the least sense of all."
"Yeah, figured," the young man replied half-jokingly. It was just something that had crossed his mind, and even he couldn't quite explain why.
Still, considering that she'd paid the price properly, all he could do was imagine that the girl had made some kind of meaningful purchase—for herself, at least.
"Uh, by the way, if you don't mind me asking—showing it to the girl who gave you that thing makes sense, but why show something like this to me, when I didn't give you anything at all?"
The question had suddenly occurred to him.
He'd come here wanting to know why that girl had left the shop—but thinking about it now, he didn't understand why the shop owner had shown this to him as well, without any compensation.
"Why? Because you're still young. It's a lesson—there are things like this in the world, so be careful. You know, if curiosity gets the better of you and you go poking around with stuff like this, things could get ugly."
"I'm not that much of a kid. I'm not going to get cursed that easily."
"Gahahaha! Fair enough!!
With an apologetic grin, the shop owner gave the young man a friendly pat on the back as he said that, and together they left the tasteless room. Afterward, the young man finished his shopping as usual and left the store—but in the end, he never learned what the girl's "purchase" had truly been.
Nor did he know, at that moment, that he would soon come to understand it all too clearly.
The adventurers who had answered the call, along with the properly conscripted soldiers, turned out to be surprisingly similar to himself. Many of the soldiers were villagers who had volunteered and undergone training, or former adventurers who had switched paths and become rookie soldiers. Talking with them before the march—discussing the future that lay ahead—was genuinely enjoyable.
After spending some time chatting with them, he even found himself thinking that he wanted to overcome the coming battlefield together with these people.
That was what he thought.
What he was supposed to think.
"A… ah..."
And yet—what was this scene?
It wasn't some fairy-tale victory where inexperienced recruits and young adventurers triumphantly cut down the demon army.
But neither was it a simple tale of being trampled and crushed by the demon horde, their dreams shattered.
If anything, both sides were being trampled.
Demon soldiers were being cut down, stabbed through, dissolving into particles of mana as they vanished.
Comrades were being struck down, killed, collapsing in pools of blood.
Both sides alike were being swept away, as if they were nothing more than dust.
Which side held the advantage was obvious.
It was clearly humanity.
Because the demon army had already been annihilated—save for a single remaining being.
If that was the case, then all that remained was for them to gang up on that lone survivor.
That should have been all there was to it.
And yet—his body refused to move.
"W-why…?"
His hand, gripping his sword, wouldn't stop trembling, clattering against itself.
The other recruits were the same—able only to stare at that existence in terror.
There was only one enemy left, and yet the young man couldn't picture any scenario in which he could defeat it.
Because the one who had wiped out the demon army hadn't been them.
It had been that lone survivor—a demon in the form of a girl.
Why she had done such a thing, he didn't know. She was an existence that had suddenly turned traitor from within the demon ranks.
That girl, whose status as a demon was thought to be the lowest, had taken advantage of the moments when the human soldiers were distracted—and one by one, she slaughtered the demons from behind.
Calmly. Methodically. As if it were nothing more than a practiced, routine task.
There was another reason the young man's legs wouldn't move.
Fragile pale-pink hair. Dark violet eyes that exuded a decadent air. Skin not yet fully matured—round and white like porcelain.
Back then, he had only glimpsed a part of her, but every one of those features matched the girl standing before him now. Revealed in full, she was just as slender and lovely as he had imagined. A reunion like this should have brought him joy—but an even greater truth overwhelmed his thoughts.
In the girl's hand was a single blade.
A sword with an organic design, as if carved from some creature's spine, wrapped in a baleful black aura.
Impossible, the young man panicked inwardly.
That blade should still have been in the shop owner's collection room. If it truly was a one-of-a-kind weapon forged by a single blacksmith, then the existence of another made no sense.
And the sheer imbalance of that ominous object resting in the girl's hand threw his mind into chaos.
The bone blade, cloaked in a black curse, was no longer satisfied with drinking only demon blood. And the girl's inorganic, dark-violet eyes—almost as if voicing its will—were now turned toward them.
It made no sense. If she had betrayed the demon army and slaughtered them all, then there should have been no reason left to fight them. If their role to her had merely been that of bait to draw the demons in, that role was already over.
Before he could even finish thinking why, it was already over.
"—Huh?"
Before he realized it, the girl was right in front of him, swinging the bone blade.
What the arc of that blade left behind was a single streak of wounds carved into the young man's body.
The bone blade—wielded with a technique so perfect it allowed no sense of presence, no reaction, not even the chance to see it—had, in the blink of an eye, slashed diagonally across his body in one clean stroke.
And then, an even greater anomaly unfolded.
"W–what…?!"
From the center of the gash, the black, malignant aura left behind within it began to spread, and at the same time the young man's skin started to change.
From human flesh, it was being eroded into something resembling the scales of a dragon.
Simultaneously, searing pain shot through his entire body.
"A—AAAAAAAHHHH—AAARGHAAAAAAHHHHH!!"
Despite bearing a diagonal slash across his torso and bleeding profusely, the young man writhed violently on the ground as though tormented by some unseen force.
Even as he did, the corrosion advanced without mercy. Proof of his humanity was replaced, one after another, by grotesque dragon scales. The curse was nothing less than the very resentment of a dark dragon that had died young—an infant dragon whose growth into a proud dragonkin, feared by humans, demons, and monsters alike, had been cruelly cut short.
A "curse" refers to a form of magic wielded by certain monsters, demons included. Its underlying magical formula cannot be deciphered, and it most often manifests as an alteration of the target's physical state. Such curses cannot be lifted by ordinary magic; to save someone whose body has been altered requires "Goddess Magic," which only priests can wield.
Naturally, there was no priest capable of using such "Goddess Magic" present here.
Thus, there was no longer any way for the young man to be saved.
Even as he clearly felt death drawing near, his consciousness did not fade. Until the very last moment, the resentment bound within the curse clung to him, manifesting as pain and refusing to let go.
Even so, within his agony-ravaged, dying awareness, his blurred vision caught sight of her back—of the girl calmly cutting down his other companions with that bone blade.
(…Ah… so she really did… go shopping properly, after all…)
Swallowed by the pain of resentment, the final thought he managed to squeeze out of his fading consciousness—self-mockingly—was about that girl of all things.
And thus, the young man's life came to an end.
This scene, too, was merely one fragment of the harvest she had carried out.
Receiving sacrifices offered up by humanity as payment, she annihilated demon armies.
Those accumulated fragments undeniably reduced humanity's losses and contributed to cornering the Demon King's forces.
And—without their ever knowing—she even carved open the path for the hero's party that would directly slay the Demon King. That this path had been paved, in no small part, by the executions carried out in secret by a demon girl and the many human sacrifices offered up to her was something they would only learn long after the Demon King had been defeated.
◇
This was not a job that novices could do.
Nor was it a job that veteran warriors or famed knights could do.
Someone once said that this was "a job that only a newcomer could do."
The task itself was exceedingly simple: one merely had to become a sacrifice. If sent out as a sacrifice, some being known as the Executor would take that life as payment and reliably wipe out the demon army.
By methods unknown to us, at that place, the demons would be exterminated together with the sacrifice.
Without telling the sacrifices anything, we would deceive them, saying this was their chance to make a name for themselves as warriors, and send them out.
Vile, isn't it? The work of devils, you might say. One can no longer tell which side is truly the demons.
There was a time when we wondered who—or what—the one called the Executor really was. And so, mixed in among the newcomers, we sent along a few warriors and mages we trusted to return no matter what hellish battlefield they faced.
But the result was this.
Even stealth techniques proved meaningless; none of them returned. Whether that was a warning message from the Executor, or simply a principle of slaying anyone who witnessed her hunting grounds, we cannot know.
Still, one day, retribution will surely come for us.
We learned the taste of it. By sending only the bare minimum of newcomers into the jaws of death, we received guaranteed results in return. Demon armies, simply by existing, devour countless soldiers and innocent civilians. By sacrificing only a fraction—one-tenth—of those who would have been eaten, we could reliably reap the demons instead.
Once we learned that taste, there was no turning back. History has repeated this countless times. Even before the Executor appeared, we had done similar things again and again. But back then, at the very least, our hearts ached. And often, even after making such sacrifices, things still failed.
Precisely because we could not be certain that results would come back—even after sending people to their deaths—we were at least able to feel pain. We were able to pray for them. We were still, barely, within the bounds of humanity.
But once we knew the results would surely come back, it was astonishing how easily even that pain vanished.
Compared to guaranteed success, the sacrifices of the young people we were about to send out felt negligible. Ah—if the Goddess who descended in the age of myth truly still watches over us from the heavens, then we are surely already being judged by her.
And yet, even knowing that, we became unable to let go of that taste.
Among the young people who were sacrificed, there were surely many who could have grown into warriors bearing humanity's future. No—there is no doubt that was the case. It should have been our duty, as the old, to protect the future of such youths. And yet, we even forgot that.
Now that, through your efforts, the Demon King has been slain and his army has collapsed, there is no longer any way to learn who the one called the Executor truly was.
And we—cut from the same cloth—have no right, at this late hour, to question the righteousness or wrongness of her actions.
So this is nothing more than the final, disgraceful struggle of an old man.
An old man who sent countless youths as sacrifices, who cast away even the last remnants of human compassion—yet who, at the brink of death, still wants to believe that some trace of humanity remains within him. A wretched self-indulgence, called confession.
Will you despise me?
You said that the Goddess forgives any sin—but would she forgive an old man who has fallen into such dark practices?
…No. Whether she forgives me or not does not matter now. If she does not, then I will simply fall into hell all the same.
Now then, I have spoken at length in confession, but in the end, there is only one thing I wished to tell you.
I know full well that I, the true culprit, am the last person who should say this.
Even so, I believed that I was the only one left who could speak of it. Everyone else is desperate to bury our deeds in darkness.
That is why I came all this way—to the church of this Holy City, where you reside.
Therefore, Bishop Heiter—
Please, remember at least this one thing.
You, the Hero's Party, did indeed slay the Demon King. That achievement will be passed down through generations long after you are gone.
But I am now the only one left who can tell their story.
So please remember this truth: that the journey which led you to slay the Demon King was, in no small part, paved by the sacrifices of the young people we old men sent out.
"..."
Having listened to the old man's confession and plea, Heiter remained silent for a while, unable even to maintain the fixed smile on his face.
◇
—Several years after the hero Himmel defeated the Demon King.
The Demon King's army had been destroyed, and peace had returned to human history—though only briefly.
Even now, the royal capital still retained the liveliness left behind by the parade held in honor of the Hero's Party that had slain the Demon King.
Hero Himmel.
Priest Heiter.
Warrior Eisen.
Mage Frieren.
A lone figure stood, gazing up at the four bronze statues erected in their honor.
Though concealed beneath a black cloak and hood, her stature and the soft contours of her skin made it easy to tell that she was still little more than a young girl.
The hooded girl looked up at the four statues without a word.
To her, these were the people who had brought an end to her days of execution.
For some reason, humans sought to preserve such achievements in the form of statues, leaving them for future generations. She could not understand what meaning there was in doing so, but she did understand that humans possessed such habits.
She suddenly wondered how that applied to herself.
In terms of slaughtering demons, she had done the same. But her way of harvesting left no exceptions—anyone who witnessed it, human or otherwise, had been cut down.
Therefore, there would be no humans to pass on her story. And it would be troublesome if there were.
Yet suddenly—the words spoken by the elven man she had once fought crossed her mind.
"If you keep doing this… who do you think will ever remember what you've done?"
Those words she had heard from behind as he departed.
Somehow, she now understood what he had meant.
Perhaps that elf, too, had accomplished something great long ago. And yet, because it was never known—or because it was forgotten over the long passage of time—those words had slipped from his mouth.
If she were to compare it to demons, it felt like honing one's magic endlessly, only for no one to ever acknowledge it.
But then she wondered—why had that elf gone out of his way to say those words to her?
Being remembered would have been inconvenient for her.
It wasn't a matter of whether her actions would be praised as achievements or condemned as atrocities—the problem was being known at all.
Of course, there had been advantages to being known to some extent. There was the tangible benefit of the enemy willingly offering up sacrifices of their own troops.
But even that truth would never be made public on their side; it would be buried in the shadows. That suited her just fine.
So she still could not understand why that elf had chosen to say those words to her.
And thus, the Demon King was slain.
She had cut down the demons who stole the people of that village from her—again and again and again—and those actions, in the end, led to the Demon King's defeat.
She had never intended it that way, not even a little. But viewed from a certain angle, her actions could indeed be called achievements… if only they had not been committed by a demon.
Her days of execution were over.
Those countless executions would never be passed down. Along with the sacrifices of the soldiers offered up, they would be buried in darkness.
There was nothing inconvenient about that for her.
If anything remained, it was only the fact that she was good at hunting demons—and good at killing people.
"..."
A sudden noise rippled through her thoughts.
The bitter, metallic taste still lingering in her mouth. Even though she had slaughtered demons without end and believed she had reclaimed her identity, it still refused to fade.
She thought she could finally take her first step toward living as a demon.
—What meaning is there in being good at killing people, for a defective product that can't even eat humans?
Only now that everything was over did thoughts she had never had before rise to the surface of her mind.
They would not disappear.
The taste in her mouth, the burning village, the farmland—none of it would leave her head.
"…What the hell is this?"
Muttering sluggishly, the girl turned her back on the statues and walked away.
Slowly, something she herself had yet to realize began to eat away at her.
Neither demon nor human.
Her body had long since been—made of swords.
She did not yet know that a mere sword has no indulgence, and no rest.