This story is told from a third-person perspective.
[Orkune Fortress] Later historians would say that the Orkune Fortress lit the fuse of the Human-Demon War.
It was generally believed that the Demon race had invaded human territory simultaneously, but even before that, a Demon race scheme had already been festering inside the Orkune Fortress.
The origin of the incident occurred one day before the Demon race launched their coordinated assault.
A certain shipment was delivered to the fortress.
The delivery was made by the unit that regularly transported supplies to the fortress.
As a supply unit that had been working diligently up to that point, no one had any reason to suspect them.
And so, the shipment was barely inspected before being carried inside the fortress.
None of them had the slightest idea it was an unthinkable time bomb.
"Hmm? What is this shipment?"
"Beats me. Nobody told us what's inside. Judging by the smell, it's probably horse feed or something?"
"Hey, wait — is this thing moving?"
"Huh? No way... It's definitely moving."
"Someone. Which unit brought this in?"
"I-I don't know. I only noticed it was already here when I... You should check on it right away. Then report this upstairs. I'll keep watch on this shipment here."
"Right. Got it."
The soldier who discovered the shipment had not reacted incorrectly.
His reaction was correct — just slightly too late.
"! Watch out!"
It burst out from the shipment.
It lunged directly at one of the soldiers, tackling him to the ground.
"Guh?!"
"A-An Anogratch?!"
What had leaped at the soldier was a single monster.
A monkey-like creature.
"What's going on?! What happened?!"
"A m-monster?! How did it get inside the fortress?!"
"We need to help him, now!"
Other soldiers rushed over at the sound of the commotion.
They drew their swords and thrust their blades at the monster attacking their comrade.
"Hold it! Don't kill it!!"
Had they been in a calmer state of mind, they might have remembered.
The terror of that creature called the Anogratch.
Pierced by countless blades, the monster died.
As if that were a signal, several more of the same species burst out from within the other shipments.
A number of soldiers who saw this realized the gravity of what they had done, their faces going pale.
"There's no going back now! Engage!"
The remaining monsters were cut down by the soldiers' hands.
Individually, they were not particularly powerful creatures.
They were no match for the soldiers stationed at this fortress, which served on the front lines of the war against the Demon race.
But that was only true when dealing with a single one.
"Report this upstairs."
"Right."
The faces of the soldiers who had annihilated the monsters were grim.
"What do we say in the report?"
"That the nightmare of the Revenge Apes has begun."
Anogratch — also known as the Revenge Ape.
A ferocious monster said to never forgive any being that harmed its own kind.
If you killed even one of these creatures, they would come swarming in massive numbers.
And they would never stop until their target was dead or the entire pack had been wiped out.
Monsters possessed by a frenzied rage.
"What's going to happen to us?"
"In the worst case, this fortress could fall."
The massive swarm of Anogratch attacked the Orkune Fortress the very next day.
It was the very same day the Demon race launched their simultaneous assault on human territory.
"That went well, didn't it?"
"Yes. Everything went off without a hitch."
The Demon race's Second Army Commander, Sarnathria, and her adjutant gazed at the distant Orkune Fortress.
Countless monkey-like monsters clung to the fortress walls, streaming inside one after another.
The humans defending the fortress initially tried to repel the monsters using magic and other means.
However, the creatures known as Anogratch kept coming and coming, no matter how many were killed, gathering at the fortress in an endless tide.
This sheer numerical violence was what made Anogratch so terrifying, and their abnormal fearlessness in the face of death was their most troublesome trait.
Once these monsters had their sights on a target, even the sturdiest of fortresses would fall like this.
"Indeed. With this, our losses stand at zero."
"That's right. Although, we won't be able to approach the fortress for a while now."
Even the Demon race did not mess with Anogratch.
They couldn't afford to attract the creatures' attention either, so until every last Anogratch had retreated, they couldn't approach the fortress even if it had fallen.
"That can't be helped. Besides, this war isn't about conquest. This is more than sufficient."
"That's true as well. But it was a brilliant display of strategy."
"Not at all."
Sarnathria truly meant that.
What she had done this time was remarkably simple.
Using the power of the Succubus race, she had seduced and brainwashed a human supply unit, then had them capture several Anogratch.
Then she had them transport the creatures inside the fortress alongside the supply goods.
That was all there was to it.
It was full of gaps, and the probability of failure was high.
But Sarnathria was perfectly willing to accept failure.
The only thing that mattered was creating a situation in which humans would meddle with the Anogratch.
She didn't even need to have the Anogratch smuggled into the fortress. She could have brainwashed other humans, had them kill one on the spot, and then simply sent that person back to the fortress with a straight face.
This time, it had happened to work on the first try, but there was nothing that could really be called a meticulous plan.
"I'm sorry, Demon King. I have no intention of obediently following your designs."
Sarnathria murmured with a melancholy expression.
The image of the Demon King surfaced in her mind.
Sarnathria possessed enough power to lead the armies of the Demon race.
Even so, she did not believe she could defeat that Demon King.
Sarnathria had no desire to oppose an opponent she stood no chance against.
She had no such desire, but it was plainly obvious that if she continued to obey, she would eventually be used up and discarded.
That Demon King was exactly that kind of being.
And so, while remaining outwardly obedient, she intended to deviate from the Demon King's plans as much as possible.
"I may be wrong as a member of the Demon race, but I'll make sure to fulfill my quota — so would you mind looking the other way?"
No one answered Sarnathria's soliloquy.