Nemusia hung her head, tears streaming down her face.

Librio san watched over her silently, his expression clouding slightly.

The Kingdom would not return.

It wasn't anyone's fault.

However, if there was a visible difference between Librio san's sorrow and Nemusia’s, it was likely the difference of whether "salvation" existed or not.

After all, even if the Kingdom perished, the Queen was alive like this.

In whatever form it might be.

"...I am powerless."

Nemusia muttered under her breath.

If she was saying that, then so was I.

The Kaigyo was an unavoidable natural disaster—the moment I learned that, I felt like such a minuscule existence.

In fact, from the perspective of the Kaigyo , we must be as tiny as microorganisms are to humans.

"But to be honest, there is a part of me that feels a little saved."

"I was just reflecting on how I had spoken of such a hopeless tale," Librio san replied.

"Thanks to you, I do not have to hate my older brother. And there is no one left in this world to hate him either. Considering the deeds he committed, do you not think he is saved?"

"Ah, yes... He is likely living peacefully in the sky by now."

Both those who had precious things stolen by Nyx san and those who stole precious things from Nyx san were no longer in this world.

Once you die, the hatred is settled.

Just like how my heart felt lighter after killing Ooki and the others.

It could be called a kind of purification.

The Kaigyo exists to clean up worlds that have increased too much and to keep the "sea" clean—if that’s the case, maybe it’s attracted to the scent of hatred because it wants to preferentially erase especially "dirty" worlds.

"Forgive me, Erika. I have spoken of nothing but things irrelevant to you."

"I’m a person from a world being eaten by the Kaigyo too, so I’m not unrelated."

"It helps to hear you say that."

"By the way, Librio san, you’re so knowledgeable because you heard about the Kaigyo from Nyx san, right?"

"Not only that. I have investigated various things based on what I heard."

"Then, I wonder if you understand what kind of state 'this place' is in right now."

"What do you mean?"

The fact that a Master existed on each floor, and that when they were defeated, the floor itself collapsed and the exit to the next floor opened.

Based on everything I’d heard so far, none of those phenomena matched the rot that occurred in the Adrasia Kingdom.

"I see... the barriers that partitioned my Kingdom. It is said that around the Master who controls them, space would distort and scenes ignoring physical laws would spread. Stretching the buildings was likely done by utilizing that ability."

"What about the fact that places outside the school are mostly not involved?"

"There is a possibility that you simply haven't recognized it yet. This is the 3rd floor, you said—even if you reach the roof above and manage to go outside, that place may already be a finished world ruled by the Kaigyo's Gangrene."

"But I—it's just an intuition, I feel like the higher we go, the closer we get to the Kaigyo's fang. In other words, I'm thinking we might be getting closer to Yumemi chan, the core."

"That Yumemi san... she is currently an existence of only a soul, correct?"

"Since her body is here, probably."

"In that case, the predation by the Kaigyo can be considered incomplete. As I mentioned before, for the Kaigyo to interfere with a world, downscaling using a core is essential."

Just as a human might think, "I'll stomp you flat!" but can't even see a microorganism to begin with—the Kaigyo needs a tool.

"In short, it rots lifeforms of the same species through an intermediary lifeform."

"Is a soul 'life'?"

"It is one form of life, but it is unsuitable as a core for the Kaigyo. A body of flesh and a soul are existences of different dimensions. If a soul were used as a core, the power the Kaigyo could exert against the lifeforms of this world might drop to one-hundredth... no, perhaps even one-ten-thousandth."

"Then it cannot prey upon us, can it?"

"It doesn't seem quite like that, though. Looking at the world as a whole, the planet Earth is just a tiny grain. Even if the Kaigyo's core-making didn't go perfectly—that wouldn't be a reason for Earth not to perish. Right?"

"Erika san is correct. Even if there is a malfunction in the predation, it has power more than sufficient to devour a single planet."

But in reality, it doesn't feel like the world outside the academy is involved.

After all, it went out of its way to bring in the Adrasia Kingdom from another world, didn't it?

Probably, Yumemi chan is controlling the predation to some extent.

So, if we ask why that happened—

"Then, it’s Giraiguu after all, huh..."

"The god worshipped by the humans here?"

"Is it not the case that they thought they summoned Giraiguu, but in fact, the Kaigyo came? Is that not why Ooki and the others were deceived?"

"No, that’s different. Both the Kaigyo and Giraiguu exist in this world. The ritual that sacrificed Yumemi chan was a success."

Ooki and the others aren't that stupid.

They only misunderstood because the ritual itself was completed and Giraiguu had been summoned.

"Kaisei kyou possessed things called 'Fragments of Giraiguu'. In other words, Giraiguu was that close even before the ritual. But since a summoning ritual was necessary, he doesn't physically exist in this world."

"Another world, you mean?"

"Not as far away as the Adrasia Kingdom. Somewhere too close to be called an alternate world, but too far to be the same world... maybe? Like a 'world on the other side'. For example, like a mirror image where everything is the total opposite."

"You are being strangely specific. Have you seen that somewhere?"

He's sharp.

To see through it that quickly, he really lives up to being a Prime Minister.

Indeed, I have seen the scene I just described.

"Hm... wait. I recall such a room as well. It was on the 1st floor of the school!"

"The place where Gii and I met."

"Then could it be... Gii, that girl is Giraiguu?"

"Yeah."

"Yeah!?"

Was it that surprising?

I don't think she was trying very hard to hide her identity.

Though she never tried to say it herself.

I felt that was just Gii’s mischievousness, or that she felt it was fine as long as I noticed.

"Wh-When did you notice that!"

"Around the time we escaped from the 1st floor, I thought that was probably the case."

"You knew from that long ago!?"

"Well, the fact that Japanese worked on Gii, who was supposed to have been sent from a different world, was already strange."

She only responds with Gii and Guu, but she seemed to understand the language at that point.

In other words, she knew Japanese.

"We also talked about how she was using the empty shell of the soul of Nanase Asami, who was supposed to have been sacrificed to Giraiguu—so I thought, 'Ah, she is a part of Giraiguu'."

Thinking about it that way, it explains why Gii feels indebted to me.

At that time, on the 1st floor, Gii and her companions were strangely confused.

Attacking me, then reconciling.

I think they were sent to a weird world just like us, and were surprised when they were attacked by the Kaigyo's Gangrene.

Moreover, Giraiguu’s main body wasn't nearby.

Probably, Gii and the others, who are just predation terminals, cannot receive energy supplies without the main body.

Cut off from food, without the power to fight, and attacked by monsters—in the midst of all that, Gii was the only survivor.

Furthermore, by fusing with a human and even gaining a name, she completely independent from Giraiguu.

Giraiguu devoured the soul of Nanase Asami, who was offered as a sacrifice.

They sucked out the contents and poured a part of themself into the remaining shell, creating Gii.

Considering that background, it wouldn't be strange for Gii, who holds a part of Nanase Asami's consciousness, to hate Giraiguu.

"I understand what Erika san wants to say. This is an interesting phenomenon; not something one sees every day."

"What are you agreeing with, Librio?"

"The 'Kaigyo' and 'Giraiguu'. Both are effectively existences equal to gods. In Erika san's world, they appeared simultaneously."

"Two gods... interfering with each other?"

Though they are in different leagues, Giraiguu has enough power to act as a god if they only facing humans.

If they collide, even the Kaigyo cannot ignore it.

"This is just a hypothesis, but when Giraiguu was summoned, I think they claimed Hikarinomiya Academy as their domain. They originally lived in a 'mirror-image Hikarinomiya Academy', after all."

That place where Gii and the others lived was their original home.

That’s probably why when offering sacrifices, it was necessary to kill them at the school or embed them in the walls.

When the worlds were jumbled up by the Kaigyo's intervention, it came out to the "surface."

"And the Kaigyo thrust its fangs into that academy and rotted it. Because Yumemi san, the core, was in an incomplete state as only a soul, that power was contained outside the academy, which was isolated under Giraiguu’s control. The amount that leaked out was very small—only enough to involve an amusement park facility and the half-rotten Adrasia Kingdom."

In a way, the domain Giraiguu created is like a balloon.

If the Kaigyo were in top form, it would have burst instantly and overflowed to the outside, but since it lacked power, involving Hikarinomiya Fantasy Land and the Adrasia Kingdom was the best it could do.

"The reason Yumemi chan became just a soul was because it was the timing to summon Giraiguu."

What Giraiguu devours are souls.

To do that, he has no choice but to extract it from the body and offer it.

It seemed Yumemi chan was treated differently from the other sacrifices, and the point was likely that she was alive.

"The ritual might have been like using a soul that had accumulated plenty of hatred and suffering—Giraiguu’s favorite foods—as bait to hook the god and pull them over here. There was something like a path leading somewhere in the basement, too."

"So, because there was a body whose soul had just been removed by the ritual, I ended up taking its place?"

"Even for the Kaigyo, an incomplete core generation would not be what it desired. However, when it tried to take it back, the physical body already belonged to another person."

Whether it tried to take it back or not is uncertain, but Nemusia dwelling in the body that should have been empty must have caused all sorts of unforeseen consequences.

In that case, Nyx san's actions were by no means in vain.

"That said, there are still many parts being filled in with hypotheses. I cannot say for certain that your world is safe based on this alone."

"But I’ll choose to believe it. It’s a stage Yumemi chan prepared for me, so it has to end with a happy ending."

In the end, that was the strongest basis.

Besides, there's no point in thinking about what would happen if we couldn't escape for the rest of our lives.

I’m finally getting my revenge and it feels great, so I want to get out safely and feel great then too, right?

"Hm? Librio... your form is fading?"

"Ah, it seems my magic power is running out."

"Then you should rest. In the meantime, shall we prepare to carry out the collection of books from here?"

"I wonder if this many will fit in my smartphone."

"I will select them when the time comes. What matters is leaving behind the fact that the Adrasia Kingdom existed here."

"You have even arranged for the transport of the books. I can go in peace now."

"Where are you going?"

"To the afterlife."

Librio san said it as if it were the most natural thing in the world.

Naturally, Nemusia was distraught.

"What are you saying! You are alive, are you not!?"

"I merely forcibly sealed my soul in a book. To be blunt, it is agonizing just to exist. Since I was able to exchange words with Her Majesty like this, it is enough."

"But...!"

"Nemusia sama."

He said, as if giving a final lesson.

"I am not dying. I am already dead. I am simply heading to the place where I should be."

His physical body had rotted away, and the soul that should have vanished with it was barely clinging to the book.

Indeed, if asked if he was "alive," it would be hard to answer yes.

But Nemusia still couldn't accept it.

"Librio... do not leave me alone."

She pleaded in a trembling voice.

"You are not alone. Your Majesty has a trustworthy 'friend', does she not?"

Saying that, Librio san looked at me.

A friend, huh... I intend to get along with her fairly well, but I wonder if we’ve built that level of trust.

At least, that might be how it looked to him.

"Even if it was for the sake of the country, you, still young, had no choice but to kill your own self to become the Queen. Seeing you witness countless conspiracies and betrayals, and becoming unable to trust people—it pained my heart. But that you, now, are opening your heart to a person from a different world, let alone a different country."

"Librio... you devoted yourself to me! I trust you!"

"I... I turned a blind eye to the plan to murder your father."

"Hah...?"

Nemusia was speechless.

I recall her saying her father had died after being caught up in a power struggle.

"By making you the Queen, I, the Prime Minister, could effectively seize power in this country."

"What... are you... saying..."

"To increase my own power, I was also moving forward with plans to marry Her Majesty to one of my relatives in the future. If that happened, I would become royalty—"

"Stop! I do not want to hear such talk!"

Nemusia raised her voice.

But I could tell.

Surely, this was exactly as Librio san intended.

"You... since I was young, you taught me so many things. As an older brother even further above me and my older brother, you played with us, talked with us, laughed with us! We spent time... like family..."

"Even so, I believe I have lived a more upright life than others. Yes, even a person like(....) me."

"Uu... uuh..."

"But you will never be caught up in such ugly struggles again. Nemusia sama, you have found a path where you can be truly happy, something you could never have obtained in the great Adrasia Kingdom."

The great Adrasia Kingdom wasn't such a wonderful thing.

So there is no need to lament—in that way, he tried to lessen Nemusia’s sorrow.

In fact, she seemed to have calmed down a bit.

Maybe Nemusia knew, too.

That the Adrasia Kingdom wasn't such a wonderful place.

"So, please do not cry. Rely on your trustworthy friend and live happily. As an individual named Nemusia Adrak."

"Librio..."

She could only call his name with a trembling voice.

Nemusia no longer had any reason to stop Librio san.

Deciding that the persuasion was complete, he beckoned to me.

"Erika san, may I have a moment at the end?"

"Sure."

In the shadow of a shelf where Nemusia couldn't hear, he asked with a serious face.

"What do you think of Ikuna Yumemi?"

"Our relationship? Well... more than a best friend, I guess."

"I thought so."

I had no idea what he wanted to say, but a single book flew out from the bookshelf and floated right in front of me.

Then it landed softly on my palm.

"I entrust this book to you."

"What is this?"

"I understand it is a selfish request. However, I absolutely do not want the Adrak bloodline to end. In whatever form."

"Bloodline... eh, um... hm?"

"If Ikuna Yumemi’s soul ever returns to her body, two souls should come to inhabit the body together. Theoretically, that should be possible."

"I see..."

"And in here, the secret arts for producing an offspring are contained. It was passed down through the royal family for generations to ensure the bloodline would not cease."

"...Eh?"

What is this person saying?

Produce an offspring? Between who and who?

"I will not force you. But when the time comes, please remember my words and try opening this book. Her Majesty should be able to decipher it."

"No, wait, does that mean in short—"

Are you telling me to make a child with Nemusia!? Me!? To preserve the Adrak house!?

"No, no, no, are you being serious!?"

"I am perfectly serious. Please take care of Nemusia sama."

I shouted to stop him, but Librio san gave a satisfied smile, turned his back, and returned to Nemusia’s side.

This guy, just because it’s the end, he intends to unilaterally push his own desires on me!?

I thought he had a sketchy face from the start, but to do something like that!

"Well then, Nemusia sama, this is goodbye. May your future be overflowing with light."

"Librio... Libriooooooo!"

They couldn't touch, but Nemusia and Librio leaned in as if to embrace.

I couldn't possibly interrupt that.

And Librio’s form grew faint—and eventually vanished completely.

Furthermore, the book placed on the desk closed and burned up on its own.

"U, ku... why speak of such things at the end. You were my family. Since you are my beloved family, it should be... alright to be honest with my sadness...!"

Left alone, Nemusia still seemed unable to organize her feelings well.

Or perhaps, preventing her from facing a sorrow that was too large was the very reason Librio san had told her those things.

Tears fell profusely from her large eyes.

She let out sobs and rubbed her eyes over and over, but it didn't stop—

"Uuuh... uwaaaaaaaaan!"

Eventually unable to hold back, she cried out loud.

It was a cry that made my chest tighten painfully just by listening.

"Nemusia..."

When I walked up to her, she hugged me tightly from her side.

"uu, uuh... I have no one but you anymore. You may think of me as a burden, but!"

"You aren't a burden. You can rely on me, okay?"

"Erikaaa... uuh, uwaaaaaa...!"

As Nemusia cried into my chest like a child—no, as a child—I lightly patted her head.

Even at a time like this, when I remembered the words Librio san said to me, all sorts of thoughts popped into my head.

Yumemi chan.

Rea.

And Gii too... she’d probably jump at the idea if she knew.

No—but, still.

Ah, no good, thinking about it won't give me an answer.

I can understand Librio san's feelings, but it's too far outside the scope of my "worldview."

I’ll stop thinking about it deeply for now.

Because Nemusia is crying right in front of me.

I decided to focus only on hugging her with both hands and healing her heart.

◇◇◇

Several dozen minutes later, Nemusia was finally able to raise her face.

Mentally she was still unstable, but she had recovered enough to stand on both feet and walk somehow.

I wonder if I was able to heal her suffering even a little with my power.

Her entire country perishing along with her family and friends—I’ve never experienced anything like that, so I don’t know how much help I was.

Still, at the point where I, who was only ever oppressed by others, could be a support for someone even a little, I truly felt glad that I had taken my revenge and killed them.

By the disappearance of the excess things from the world, I was finally becoming a normal human.

We stuffed the books stored in the archive into my smartphone one after another.

For now, the capacity limit wasn't in sight, and we managed to put all several hundred thick volumes in.

It didn't become particularly heavy either.

Was this also utilizing the Kaigyo's power?

Having finished our business, we exited the archive cautiously.

From all over the castle, the voices of adults playing innocently could be heard.

But as expected, there were no students to be seen.

We proceeded toward the exit through the eerie interior of the castle, which felt somewhat chilling.

There was a suggestion to explore the inside of the castle, but for now, I wanted Nemusia to rest.

Unfortunately, the path we came from was blocked by teachers absorbed in a ball game.

"I guess we have to find a different way."

"Or we could just kill our way through."

"I thought about that too, but I don't know where Marin and the others are, and I want to avoid confusion right now. Truthfully, I want to kill them this instant, but it would be troublesome if they regenerated like the Casts."

"I see, your younger sister and her friend were also out for a walk, were they not."

"Everything except this building Librio san protected is mostly rotten. If so, those two's destination is likely here in the end, after all."

"It would be good if we could meet up."

If she were thinking of meeting up, I don't think she would have gone out with just the two of them from the start.

If my guess is correct, Marin probably—

"Hm, those people seem to be coming this way."

"The path on the right, can we get out from there?"

"No, that only leads toward the throne room. But there are no other escape routes."

I want to avoid moving further from the exit, but there’s no choice right now.

We silenced our footsteps and moved toward the throne room.

During that time, I was observing Nemusia’s expression, but I was relieved to see that she didn't seem to have any trauma regarding the throne room itself.

When we arrived in front of the doors, a savory smell drifted from within.

I peeked in through the slight gap.

Inside, adults clad in rags were making a fuss around a bonfire.

"What are they doing..."

"They are in high spirits, huh; do they believe this place is a paradise? To use the throne room for a banquet, what a disrespectful lot...!"

"Moreover, they’re roasting something. I thought everything was rotten; does that mean the food inside the castle remained?"

"I do not think that is the case. By the time I was killed by my older brother, the provisions were almost completely exhausted."

"Then that is—"

"They must have procured it from somewhere."

If so, did they bring it from some classroom?

But was there any place on the 3rd floor that would have food?

The home economics room is on the 1st floor, and the staff room is on the 2nd floor, right.

"Erika, is that over there perhaps—"

"Ah, Marin and Hiyami san."

At the back of the throne room—beyond the group singing and dancing around the bonfire—were the two of them.

They were talking about something with a man with well-defined features.

"Who is that?"

"Setaguchi Ataru. The teacher who was the homeroom teacher for the 3rd years."

Setaguchi was familiarly putting his arm around Marin’s shoulder.

Hiyami san was staring at him with eyes brimming with cold anger, the kind she never showed to us.

But Marin herself had an anxious expression, looking somewhat weak, unlike the Kuragane Marin who was treated like a prince.

"Shall we charge in too?"

"...No, let’s not. Looking at them, Hiyami san will drag her out if anything happens."

In the first place, if that were something disadvantageous for Marin, Hiyami san would stop it first.

The fact that she didn't stop the encounter with Setaguchi while being that furious means there is a reason she has to do so.

Setting Marin aside, I think Hiyami san is trustworthy, so I’ll leave it to them.

I’m also worried about Nemusia, so we’ll prioritize escaping.

Moving away from the throne room, this time we head for the exit for real.

We found a window where there was no sign of people nearby and that looked jumpable.

We quietly broke it and escaped outside the castle.

"Phew... we managed to get out without being spotted, then."

"Next time we’ll bring everyone and attack. We can find out those guys' true identities from Marin or Hiyami san, okay?"

"Umu, but... it looked as if they were being welcomed as allies."

"Marin is supposedly an executive candidate, and Hiyami san used to be one of Kaisei kyou’s people too. If they don't know they betrayed them, getting in should be easy, shouldn't it."

"Then, did they infiltrate for information gathering?"

"It might be different. It’s likely Marin’s personal circumstances. Well, I’ll probably be dragged into it soon enough anyway."

"I do not quite understand."

"You don’t have to think about difficult things, Nemusia. Leave it to me for now and prioritize calming your mind."

"...Right. I shall take you up on those words."

"And so, let’s get back quickly. Our numbers have increased, and we have to think about what to do for food while we're here too."

Nemusia and I moved away from the castle as we talked.

Then suddenly, she, walking beside me, looked back as if reluctant to leave.

And froze just like that.

"What's wrong, Nemusia?"

"Th-That..."

She pointed to a room inside the castle.

Visible through the window was a room that was exceptionally red.

Straining my eyes, something was hanging inside.

"Are they hanging... humans?"

"Their heads have been removed, and they are being hung upside down. It is as if they are being bled out."

"Don't tell me those guys—"

The students who were nowhere to be seen.

The food that shouldn't exist.

And the corpses of the hung humans.

I felt an intense disgust and a chill.

But immediately after, I felt a piercing bloodlust.

"The man in that room is looking at us."

Looking down at us from the window of the room where the corpses were hung was a blood-covered, shirtless man.

I don’t remember his name, but he was definitely a teacher at the academy.

He looked to be in his mid-thirties.

The look in his eyes wasn't one of murderous intent, but rather of joy at having found his prey.

"Run Nemusia, he's coming!"

The man, holding a blade like a butcher's knife, jumped out of the castle through the window.

Gripping Nemusia's hand, we hurriedly left that spot.

Then the man landed slightly behind us.

It must have been a considerable height, but he was unharmed as if it were natural.

And when he stood up, his chest suddenly bulged out.

"O, obo, go... o...!"

"What is he planning to do...?"

"The only thing that's clear is that he isn't human anymore."

The bulge in his chest moved to his throat and was finally vomited out of his wide-open mouth.

A black, viscous liquid.

It looked similar to the black slime that Ooki and her group used, or perhaps the slime that made up Gii's body, but it differed in that it "emitted a foul odor."

Eventually, that mucus completely covered the man's physical body, transforming into a black armor that looked like a full-body suit.

His appearance, with a hunched, forward-leaning posture and shoulders moving up and down, reminded me of a wild beast despite being humanoid.

"Suddenly his appearance looks strong."

"Do we have no choice but to fight in this situation?"

"Well, he’s ready for it too."

In the next moment, the enemy's figure vanished from sight.

I gripped Dreamer and unleashed a slash behind Nemusia.

Above her head, blade and claw scattered sparks.

Fast—Nemusia probably couldn't see it at all.

Furthermore, at this close range, countless slits opened in the black-suit guy's face, opening all at once.

Revealed from within were red eyes.

And the eyes accumulated light, looking ready to fire at any moment.

"Nemusia!"

"I know, Air Burst!"

When I called her name, Nemusia unleashed magic as she turned around.

Goooh! An intense wind bomb exploded at point-blank range.

Receiving a direct hit, the black-suit guy was blown away, firing countless light beams in random directions as he went.

Each band of light was thin.

But there were as many scattered in random directions as there were eyes on his face, and their power was more than sufficient despite their appearance.

Touching the ground, they melted the earth red; touching trees, they evaporated and vanished them in an instant.

"Scary..."

"What is that monster. Is it the Master of this floor?"

"We’ll have to defeat it to find out. Nemusia, please attack from far enough away that he can't close the distance in one breath."

"The opponent is small as well as fast. My aim may not be accurate at long range, but is that alright?"

"Just restricting his movement is enough!"

I rapidly approach the enemy, who was regaining his posture where he had been blown away.

As the opponent noticed my movement, he also closed in all at once with that swift movement.