Project Necro is an official initiative by Re:Library.

At Grünstadt Castle, a coronation was to be held for the succession of the Demon Lord. They couldn’t very well skip all ceremonies, so this was at least a token formality. It also served as a memorial for His Majesty the Demon Lord.
After the succession, my master had decided to make Lüenheit her base of operations.
This might be the last official event to be held in Grünstadt.

On the night before the coronation—
I was listening to my master speak in one of the castle’s chambers.

“A Demon Lord is not simply ‘the strongest demon.’ They must be a transcendent, one who wields power equal to the gods themselves.”
“Even so, Master, no matter how strong you are, you can’t become like His Majesty.”

It was true my master was among the greatest magic users alive. But she was still bound within the limits of humanity and demonkind.
Not the godlike strength that the Demon Lord possessed.

Master nodded at my words and continued.

“That much is so. Yet to bear the name of Demon Lord, one cannot afford to faint merely from casting spell after spell.”
“Ordinary people can’t even chain-cast in the first place…”

The problem was that even if you tried to cast repeatedly, you couldn’t quickly gather the right type of mana. You always had to wait a little.
It was much like the ‘cooldowns’ set on spells and special techniques in games.

“But, you see, I do have a way to deal with my mana exhaustion.”

Those unexpected words from my master startled me.

“There’s such a method?”
“Indeed. If it succeeds, I too may gain power to rival His Majesty…”
“To rival…?”
“…Perhaps.”

That sounded terribly vague.

“I should have tried it long ago, but His Majesty was always so cautious, he forbade it outright.”

What’s that supposed to mean?

Frankly, I didn’t think my master needed to get any stronger.

“Master, you weren’t chosen as Demon Lord just for your strength.”

The First Division followed her because of the deep trust between her and the late Demon Lord.
The Second Division followed her because of her kindness—she had saved them twice over.
The Third Division followed her because of her character.
Each had different reasons, but they all accepted her as king for reasons beyond raw strength. In fact, I doubted many of them cared much about that at all.
If so, this might be the first time in demon history that a Demon Lord was chosen for something other than strength.

But Master shook her head.

“I know that well. Yet for that very reason, I cannot allow myself to die carelessly.”

She rubbed her throat, eyes drifting into the distance.

“Every time a king dies, his retainers are shaken. If a second Demon Lord were to perish so soon after His Majesty, then his ideals would slip even further away.”
“Well… yes, you’re right about that.”

If Master were to die now, it would surely crush the already grieving army even further.

Then she smiled warmly and went on.

“Rest easy. I’m not about to gamble recklessly. In theory, there is no immediate danger.”
“That phrasing really doesn’t inspire confidence, you know.”

Master gave a wry smile.

“You worrywart. Listen carefully. I’ll explain everything to you now.”

And because I’d said too much, a lecture had begun.

“Necromancy is not merely sorcery. It is philosophy. It is a way to confront death.”

She held a small hand over the flame of the candelabrum as she spoke.

“And necromancers speak of something called the ‘Last Door.’ Do you know what it is?”

The final door that one who faces death must open…

“Is it… one’s own death?”
“Well surmised.”

She smiled at me with a childlike face.

“Even one who calls themselves a necromancer must die so long they have flesh. At that moment, their true worth as a necromancer is tested. How does one face one’s own death?”

Master had once come close to dying, but she had not died. In our previous world, it would have been like lying in bed on life-support. Though barely, but still alive.
Which meant she had not yet opened the ‘Last Door.’

As if reading my thoughts, Master nodded.

“When I meet death, all of me will be laid bare. The ultimate question—‘What is life? What is death?’—shall be asked of me.”
“That’s… quite a question.”
“But I’ve lived long. I have, in my own way, reached an answer.”

With a chuckle, she hopped lightly down from the chair.

“Yet once I open that door, I can never return. And I cannot deny the chance that it may warp my very personality.”

Just where is she going with this?
She looked up at me with a serious expression.

“That is why, for safety, I need your help, my disciple.”

“Wouldn’t Senior Merene be better for that?”

She shook her head.

“This task can be entrusted to none but you. The one who aids me must be a full-fledged mage, and also skilled in arms.”
“Another one of those things, huh…”

Among the Great Sage Gomoviroa’s disciples, I was the one most used to rough-and-tumble business. Well, I was a werewolf.
That’s why I had always been dragged into these terrible experiments and rituals, despite being a battle-mage.
Fine then. I’d help her.
This is for Master’s sake.

“All right. But please, no more devil summoning on me, okay?”
“So obstinate. That was an accident.”

Being hounded day and night by some devil summoned from another dimension, attacking endlessly with monstrous fury—that was a nightmare I never wanted to relive.
I thought it would vanish at dawn, but no, the damn thing kept attacking him all the way into the following day. Try being the one forced to defend her!
If I ever saw that thing again, I’d rip it apart for sure.

Master cleared her throat to cover her embarrassment and declared:

“This time is simple. Come with me to the underground laboratory.”
“Underground?”
“And I’ll tell you a little story while we’re at it.”
“Stories from old folks always go on forever…”
“Just so you know, this will be a precious special lecture from the Great Sage Gomoviroa.”

Her voice echoed down the spiral staircase of the castle.

“Once, there was a small human kingdom here. The kingship was held by a family of mages. They used their magic to defend their realm from demons and foreign armies.”

But that kingdom, too, was undone by war between humans, she said.

“They trusted too much in sorcery. They drowned in power and forgot what truly mattered. They forgot that nothing is more fearsome than human hatred.”

The king’s arrogance bred resentment in his courtiers, and by their betrayal, the kingdom was destroyed with shocking ease.

The castle was surrounded by traitors, and every last member of the royal family was slain.

“Save for me. My mother cast a spell of false death upon me, and so I lingered in a state of suspended life until I recovered.”
“I see… wait, what?”
“What is it?”
“Master, this is your birthplace? So you’re a real princess?”
“I was of a collateral line, not in line to inherit. But yes, I was royal blood.”

That was the first I’d heard of it. Astonishing.

Master just shrugged, as if it were nothing.

“Did you never wonder how the Demon Lord’s army so conveniently acquired this abandoned castle?”
“I figured someone just stumbled upon it…”
“In truth, it was mine. I was the Demon Lord’s landlord.”

So this was rental property all along.

“Well, the country had already fallen, the towns and fields buried beneath forest. I thought it a fine hideout.”

At the base of the spiral staircase, Master stopped before an ancient door.

“My throat was pierced by a spear, and like the rest of my kin, my body was put on display. When my consciousness returned years later, I was drowning in fear.”
“That must be horrible…”

It must have hurt. It must have been terrifying.

“What shocked me most was to find the country itself gone, the land in ruins. Whatever befell them, the traitors had won no prosperity.”

Perhaps there had been civil war. If so, it was no less than they deserved.

“The rest of my kin had rotted to bone. And my wound had healed around the spear lodged in my throat. When I tried to remove it, the wound tore open again—I writhed in agony for three days and nights.”

Now I understood why Master feared humans more than demons.
With such an experience in childhood, how could one not?

Master lived alone in the ruins for years thereafter.
Though the castle was destroyed, many rooms remained inhabitable. And for a child, the outside world was far too dangerous.

“Day after day, I sat alone, thinking. Why had this come to pass? I delved into necromancy, seeking to bring Father and Mother back.”

But of course, that was impossible. The irreversibility of death was absolute. No art of necromancy could restore the dead.
One could summon the spirit of the departed, yes, but at best, it would flicker briefly as a ghost before fading away again.
And so Master lost her purpose in life, becoming nothing but a vessel to live on endlessly and study death.
She did not meet another soul again until more than a century later.

“At that time, I still had no answer for the ‘Last Door.’ But once I was called a Sage, once I took on disciples… at last I found one.”
“Is that so?”

Master chuckled and looked up at me.

“And the one who gave me that answer was you.”
“Me?”