The Mysterious Child: An Adventure Tale Beginning with Numerology

"Sand Dust Domain!"

Saturn enveloped himself with all the nearby sand, creating a giant armor.

Furthermore, he manipulated the sand dunes surrounding the castle, directing them towards us like a tsunami. With such overwhelming volume, we would likely be engulfed without any means to resist.

But that was exactly what I was aiming for.

"Seori! Come!"

I shouted towards the sky, sending a signal.

Far up in the sky, overlapping with the sun, Seori in dragon form was falling straight down.

Actually, she had gone outside once using the transfer device on the upper floors and had been hiding in the sky.

On her back was Nagi.

Straddling Seori like a dragon knight, Nagi swung his sword towards the approaching sand dunes.

"Oni Imagination Style -- 'God's Departure'!"

Nagi's weapon [Evil Blade: God Cutter] can erase any magic formula or skill.

It was the worst possible enemy for Saturn, who could control all sand.

The sand dunes hit by Nagi's strike returned to being just sand, and the magical power contained within them dissipated.

Naturally, manipulating all the surrounding sand like this must have consumed a considerable amount of magical power.

While it might boast unparalleled strength as an area attack, before Nagi, it was just a big target.

"What!?"

Seori approached the sand controlled by Saturn, and Nagi kept cutting it down.

Just that alone.

Saturn's trump card crumbled easily. Either he didn't have enough magical power left to manipulate the sand dunes again, or he realized it would be futile as long as Seori and Nagi were outside. He immediately released the power he had been directing outside the castle.

Saturn, clad in giant sand armor, looked down at me with a bitter expression.

"I won't let the likes of you interfere!"

From all over the giant armor, sand rained down like spears.

"Punisuke, shield mode."

"Yes, nano!"

The shield of Punisuke, who had evolved into a mithril slime, didn't receive a single scratch.

And of course, just because he became mithril doesn't mean he lost any of his previous abilities.

"Whip mode, 'Scorching Whip'."

"Leave it to me, nano!"

I wielded the mithril whip glowing with intense heat.

It easily blew away one of Saturn's sand armor arms. The hardness that Punisuke had been lacking before was now fulfilled with his mithril body. His speed and power had improved dramatically.

Of course, Punisuke wasn't just watching either.

While I swung the whip, he was also firing bullets from the wing-like parts he had grown on his back. The mithril bullets shattered Saturn's armor into pieces with enough force to kick away sand mountains.

"Flash Step!"

"Too naive, nano!"

Saturn abandoned his sand armor and used his high-speed movement skill to get behind us.

But we had already figured out the trick to this movement skill. While it's a teleportation-level quick movement, it seems he can't stop unless he decides on a landing point in advance because it's too fast. We could easily predict where he would appear by following his line of sight when activating it.

Punisuke wrapped his whip around Saturn's legs and slammed him into the wall.

"Guh!"

The wall caved in, and Saturn bounced back, spitting blood as he fell to the floor.

It seemed he had taken considerable damage, but as he fell, he unleashed a skill towards me. This time it was a skill that affected the mind.

Well, mental attacks are easily nullified by my "Cool-headed" skill, so it didn't mean much.

I approached Saturn, who had collapsed.

"Your trump card has been sealed, and you can't do anything against the evolved Punisuke. The match is decided, isn't it?"

"Guh... What are you saying? I'm still alive."

"No, there's no need to fight to the death, is there?"

I was exasperated.

My original goal was to persuade him not to target Saaya. And to get back what was stolen. If those conditions were met, I had no intention of killing him.

...At least, I didn't.

Saturn, while still coughing up blood, slowly stood up with a sneer.

"I won't give up... Making concessions to the likes of you is unthinkable."

"Why? Isn't it better than dying?"

"Don't make me laugh. Do you think death is a threat to me-- guh"

Sensing that Saturn was about to use a skill, Punisuke shot through his shoulder with a gun.

Saturn could no longer even stand properly, falling helplessly.

"Is it more important than dying? Your goal, I mean."

"Of course! My life was dedicated for it long ago."

"To that extent? Well, if negotiation is impossible, I'm prepared to go through with it... By the way, what is your goal? What do you want to do by interfering in various places and kidnapping the Ruin Factor?"

"Hmph, why should I tell the likes of you?"

"Come on, look at the situation."

The castle was half-destroyed. The sand dunes were in tatters.

The subordinates in the castle had been annihilated by Nagi, and the soldiers outside had been swallowed by the sand dunes and wiped out.

There were no more allies, and he was literally a sand king lying in a castle on sand.

"...Even so, it's not something I need to tell you."

"You're stubborn. Well, if you don't want to talk, that's fine. It was just meddling on my part."

"Hmph, you self-righteous child... You're just blessed with luck."

"Indeed, I am lucky. But what's with your attitude? 'The likes of you' this, 'the likes of you' that. Aren't you looking down on me too much? I'm carrying the title of the Mystic King's top disciple, you know--"

"Don't you dare call yourself the top disciple!"

Saturn roared.

I was taken aback by his intensity.

"Huh... what do you mean?"

"You ignorant child! Don't speak as if you know about the teacher! You're just a carefree brat who receives teachings passively..."

"Teacher... Saturn, were you also a disciple of the master?"

"...Hmph, so what if I was?"

"But the master seemed to say she didn't know much about you."

"That's because I stole her memories a thousand years ago."

Saturn muttered regretfully.

It was certainly news to me. Come to think of it, the master said she only had memories from a thousand years ago, despite living for who knows how many thousands of years.

I see, so they were stolen by Saturn's skill.

"What happened a thousand years ago?"

"I have nothing more to say to you."

"...Well, if you don't want to talk, that's fine. I don't have a habit of trampling on other people's memories anyway."

Though I am curious.

And even if I knew, nothing would change.

Perhaps surprised by my easy withdrawal, Saturn showed a puzzled expression.

"Aren't you angry? You're a disciple too, aren't you?"

"But it's all in the past, right?"

"You heartless fool. It's because you humans are like this that the teacher continues to suffer."

"Suffer... Oh, you mean wanting to die? Indeed, I couldn't understand the master's suffering, but her wish has been granted now, so isn't it unnecessary to say such things?"

"...Huh?"

Saturn let out a dumbfounded voice.

"What did you just say...?"

"I said, the master is no longer here."

"Impossible! 'Universal' is an immortal skill. There's no way the teacher could die!"

"'Universal' is numerology. You must have heard of it in your thousand years of life, right? Numerology is the only skill that changes... The master's 'Universal' is gone now. Along with the master's body."

If Saturn was indeed a senior disciple, it should be fine to tell him this much.

The immortal Mystic King had already changed her existence into a single heart.

"Saturn, I don't know what kind of feelings you had as the master's disciple, or why you said you wanted to kill the master. I also don't understand why you came after us, her other disciples, and if you're not willing to tell me, I won't force you to... But let me say one thing. Whatever your reasons may be, we are carrying on the master's will as adventurers. The master's last words to us were 'live freely'. I won't let you take away that freedom. I won't let anyone take it away."

"............"

Hearing my words, Saturn stared blankly at the ceiling.

What he managed to squeeze out was just one sentence.

"...Is the teacher really dead?"

"Yeah."

"I see... So her wish had already been granted..."

Tears spilled from his eyes.

Saturn's stern expression changed, becoming clear as if a possession had been lifted. He slowly closed his eyes and murmured.

"So the teacher was saved."

"Who knows. But she seemed satisfied when she disappeared. ...Hey, when you said you wanted to kill the master, did you mean you wanted to save her? From the suffering of immortality?"

"...I've been living for that all this time. I became a high-ranking demon, was called one of the Six Demon Lords, gained power and status, but it was all trivial compared to the teacher's suffering. I just wanted to be her hero... her one and only hero. Even if the teacher forgot about me, if I could save her, that would have been enough."

"I see."

Saturn's state of mind, as he murmured quietly, was probably beyond my comprehension. After all, he's saying that the reason he lived for over a thousand years was to save the master.

And having lost that purpose, he had also lost the will to fight.

"Boy, what's your name?"

"It's Ruruk."

"Ruruk, huh... Hmm... Human names are hard to say."

"Saturn isn't much better, you know."

When I retorted like that, Saturn smiled faintly and fell silent.

Just then, Seori and Nagi descended.

Seori transformed from dragon to human form and stood behind me as if hiding, while Nagi slowly placed the tip of his sword against Saturn's neck.

She looked down at the prostrate Saturn with a gaze full of killing intent.

"Nagi and the others are the winners," said Seori.

"You're Gale's kin, aren't you? Indeed, I've lost. Go ahead and kill me," Saturn replied.

"Yes, I will kill you. But before that, let me ask you one thing. Why didn't you forcefully order Nagi? Nagi is your familiar... he couldn't have disobeyed if ordered," Nagi asked.

"It was a deal with Gale. When I made the subjugation contract with Gale, we made mutual oaths. Because of that oath, I couldn't forcefully order you... That's all there is to it. I have no interest in you personally."

"I see."

Nagi's expression turned lonely as she put strength into the arm holding his sword.

"...Hey Nagi, it might seem like I'm not reading the room by saying this now, but why don't we leave him?" I suggested.

"It's not 'might seem like', you're definitely not reading the room. As expected of Ruruk," Nagi replied.

"Ugh, well that's true, but... I mean, revenge doesn't have to be just about killing, right?"

"Don't stop her, boy. Either way, I'm going to die soon," Saturn himself stopped me as I tried to stop Nagi for his sake.

"The things stolen by 'Usurpation' are set to be released when death approaches. I've accepted death now. Your mystic arts should return to you soon. Of course, the released things include lifespan... This body should have decayed long ago. The lost power will never return. I probably have only a few hours left to live."

"...I see."

"Gale's kin, I leave the mercy of killing me to you."

"I would have done it anyway, as it's been Nagi's role from the start."

Saturn closed his eyes again.

His body was visibly aging rapidly.

"Do you have any last words?" Nagi asked.

"Let's see... Ruruk. As the teacher's last disciple, live a life that wouldn't shame the teacher. That's all I wish for."

"Yeah, I understand."

"Then, sorry for keeping you waiting, Gale's kin."

"I will grant you a painless death, as a mercy."

Nagi slowly raised her sword.

There was no dark stagnation in her eyes anymore.

Only deep sadness was wavering there.

"...Brother, Nagi will join you soon," she murmured as she swung down the sword, easily severing Saturn's head.

I watched this scene without averting my eyes.

He was undoubtedly an enemy, a high-ranking demon.

But at the same time, he was a fellow disciple.

Because he was a disciple who loved the same teacher, I couldn't look away from his death.

Saturn's body turned to sand as soon as he died.

It was a body that should have decayed hundreds of years ago. Perhaps it was a fitting end for the Sand King.

The sand was blown by the wind, dancing up into the sky.

And so, our connection with Saturn came to an end...

"--Wait, is it shaking?"

As soon as Saturn turned to sand, the castle began to rumble and shake. Why is it suddenly about to collapse?

Nagi calmly said, "Perhaps because the Dungeon Master died?"

"Damn it! You should have mentioned that possibility earlier, you bastard Saturn!"

Or maybe he deliberately kept quiet. To drag me down with him.

Well, escaping isn't difficult. It seems my stolen mystic arts proficiency has returned, so I can use teleportation right away.

"Alright, let's escape. Grab on, Seori, Nagi."

"Y-Yes, my lord!"

"Hey Nagi, you too, hurry--"

"What are you saying?"

The already crumbling ceiling was slowly falling apart.

Nagi stared blankly at the scene and said,

"I've been saying it from the beginning. Nagi will die after achieving revenge."

"That's true, but! There's no need to get caught up in the castle's collapse! Just hold on a little longer, at least until we get back--"

"Either way, we familiars of Saturn will die in a few minutes."

"Huh?"

What does she mean?

What is she saying?

"Saturn's subjugation contract has strict constraints. If Saturn dies, all familiars are set to die a few minutes later. Moreover, the process involves experiencing unbearable pain before death. That's why no one could betray Saturn."

"W-Why didn't you say anything! Why didn't you tell us!"

"It wouldn't have changed anything. There's no need for sympathy when I'm going to die anyway."

As Nagi said this, she was already sweating, perhaps from the pain that had begun.

"Now, go. Nagi is already a dead man... Ruruk is an idiot, but he shouldn't be stupid enough to die just to watch over Nagi."

"Don't be ridiculous! There's no way I can accept that!"

"Besides, even if I survive, Nagi is defective. There's no place for Nagi anywhere."

"I'll make a place for you! So, so..."

"I see. Indeed, Ruruk is kind. Just like my brother."

Nagi showed a smile for the first time.

Her eyes, which had been tainted with revenge, shone with a beautiful cobalt blue, if only for this moment.

There were faint tears in those eyes.

"Seori has a good master. Ruruk, Seori is a good child. Make her happy, absolutely."

"What are you saying--"

"Go, please. It's painful for Nagi to endure any longer."

Nagi grimaced, clutching her chest. She showed no sign of listening to my words.

I couldn't persuade her.

Having finished her revenge and with no will to live, is she going to be killed by the subjugation mark like this?

Had Nagi been prepared for this kind of farewell from the beginning?

Damn it.

Nagi is by no means a good person. Even if it was for revenge, she kept killing and killing.

Surely in this world, there would be no one to side with such a demon of revenge. If it's a matter of justice or evil, she's definitely evil. I understand that much.

But I didn't dislike Nagi.

A demon girl who was just sharp-tongued, cheeky, and fatally brother-complex -- that's who Nagi was.

In this short journey, I arbitrarily thought we had become friends.

I thought we had become friends.

I couldn't just silently watch such a person die.

I don't mind being resented. I don't mind being hated. Still, I wanted to save Nagi.

It's just my ego. From the perspective of those Nagi killed and their families, I would be considered a villain. But so what? I didn't want to be the kind of man who couldn't save even one friend right in front of him.

"Qu-Quickly... go, please."

"No! I'll definitely save you!"

"W-Why, why go so far..."

"Because you don't want it! You've been saying all along that you intend to die, but you never once said you want to die! Only a real idiot would silently watch a friend who doesn't want to die, die!"

Is there anything?

Something to save Nagi.

As I was desperately racking my brains, suddenly, Seori stood in front of Nagi.

Then she casually opened the bottle she was holding and poured a purple liquid over Nagi.

-- That's it! The curse-breaking potion!

Nagi, doused with the curse-breaking potion, widened her eyes and lifted her shirt.

The subjugation mark that had been carved below her chest had disappeared completely, as if it had never been there.

The pain seemed to have disappeared too, leaving Nagi utterly confused.

"Huh, why..."

"Master!"

"Right! 'Relative Teleportation'!"

Grabbing Nagi, who had been freed from Saturn's curse, we all teleported to the desert.

Immediately after, the dungeon collapsed. The castle crumbled and the rubble was swallowed by the quicksand.

It was a close call.

Taking a breath and looking back, I saw Seori slap the dumbfounded Nagi's cheek.

"You're an idiot too!"

"Huh..."

"If you don't want to die, you should say you don't want to die! You thought you shouldn't live just because you killed a lot, right? It's written all over your face!"

"W-What's with you suddenly... What does Seori know about Nagi!"

"I do know! I wanted to die too! But the master saved me!"

Seori was crying.

Unable to contain her emotions, she grabbed Nagi's shoulders and shouted.

"Besides, we're comrades now! We can't just leave a comrade to die!"

"Wh-What do you mean comrades... Nagi is a demon. Just because we traveled together, sympathy is..."

"It's not sympathy! And, and... we're friends! It's natural to save a friend if they're going to die!"

"..."

Seori's face turned bright red, perhaps embarrassed to say it herself.

Nagi was frozen at those words.

I patted Seori's head and said,

"I feel the same way, Nagi. If you don't want to die, if you can avoid dying, isn't it okay to live? I'd be sad if my friend died, and even more so if it's you, Nagi."

"Even Ruruk... When did Nagi become friends with you all?"

"What's that? Are you dissatisfied with being our friend?"

"...It's not like that, particularly."

Nagi turned her face away.

She's really not honest at all.

"And it might sound presumptuous, but that potion just now was extremely valuable, so I'd appreciate it if you didn't say anything more about dying, to avoid wasting it, you know?"

"Come to think of it, what was that? The pain disappeared immediately and the subjugation mark vanished too. The notification area also said I was released from subjugation..."

"It's a curse-breaking potion. It seems to have the effect of nullifying oaths and curses. Probably as valuable as an elixir... though you might not know what an elixir is. Well, to give you an example, if you sold it, that one bottle could buy a house."

I was actually planning to use it on Seori.

Well, it can't be helped if it's already been used, and you did well.

"...If you say that, I can't die so easily. You're really selfish, aren't you?"

"That's right. So Nagi, please live for now. That's my only request."

"Hah, I understand... But I have nowhere to go. There's no place that would accept a defective product like me."

Nagi said this and looked up at the sky.

It was already dyed with the colors of dusk. It would soon be night.

I'm not irresponsible enough to abandon her here.

I reached out my hand and said,

"For now, let's go back to the Elven village. Maybe our companions are still waiting for us."

"Eh, Nagi too?"

"Well, you don't have anywhere to go, right?"

"B-But Nagi is a demon, and suddenly being attacked..."

"It's fine, it's fine. We'll manage somehow."

I said this casually and teleported everyone.

At the last moment, I glanced at where Saturn's castle had been, but the rubble had all been swallowed by the quicksand, leaving only a desert no different from the surroundings.

And so, we ended our journey in the demon realm.