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There are exactly seven Demon Lords.

And among these seven Demon Lords, the strongest is obviously me, Belphegor.

So, who is the most troublesome opponent I have to deal with?

It’s not that it’s hard to fight against them, nor is it that I lack something when facing them, but purely due to environmental factors, there is one being that is quite troublesome.

Demon King Leviathan.

Also known as the Witch of Jealousy, the Sea King, the Goddess of the Sea, and referred to as the ‘Sea Dragon’ woman.

Although I referred to her as a woman, the body she uses for battle in the Demon World is a gigantic serpent over 300 meters long.

Rather than calling it a serpent, let’s call it a sea dragon.

In any case, this sea dragon Leviathan displays her utmost power in the environment of the sea, where naturally, the strength of land-dwelling creatures diminishes significantly.

There’s the issue of breathing, and the very environment of being underwater makes it quite awkward for those who were used to fighting on land.

If fighting in the sea isn’t ideal, then can’t we just fight outside the sea?

If you ask that, Leviathan would never engage in battle outside of the sea.

– Coward!

– What’s cowardly about only fighting in a place where you can do well? If you want to, come into the sea!

– Ugh, cowardly!

So, battles with Leviathan were always fought under the assumption of ‘the sea.’

In fact, when I fought her, I had to dive into the water to pull her out before I could really deal damage.

However, how is she now in the Intermediate Realm?

And she even arrived a year before me?

“Did you happen to see any marine monsters on the way?”

“I did. They’re more angular than 500 years ago. They must have evolved over those 500 years.”

“Those are external armors. They’re wearing protective shells and armor over their original bodies. If they don’t, they’d all be swept away by Leviathan’s forces.”

Celcius sprayed water mist in the center.

The scene that played there unfolded like images from a magic stone, and I quickly realized this was something that happened underwater.

Kyaaaahhh—!!

A massive legion of marine monsters.

Crabs, sharks, seahorses, sea dragons, krakens, and a countless number of marine monsters were approaching Belselphia.

So how is Belselphia dealing with it?

“I’ve wiped them all out until now.”

Celcius eliminated them.

With a flick of her finger, a massive number of marine monsters approaching Belselphia were swept away all at once.

“Indeed, the source of the Holy Sword. True to the roots of water attribute power.”

“To protect my children in Belselphia, this much is necessary. They’re your subordinates too, right?”

“…Yeah. Thank you.”

While defending her territory, Celcius also protected the remnants of the Demon King’s Army and the human collaborators—whom I would like to call pro-Demon King faction humans—within her domain.

As the ruler of this city, she could have directed the residents to confront those monsters, yet she took action herself to battle the beasts.

“Demon Lord, this is indeed challenging. All the well-known sea monsters in the deep have consumed the surrounding sea water and turned that power into their own. Even the Sea Dragon was one of them.”

“Really?”

“Yeah.”

The Sea Dragon.

Also referred to as ‘Blue Dragon,’ it is a true dragon species, like the Black Dragon I was using.

“Although it takes on the appearance of Leviathan, its power is that of a Sea Dragon, right? It’s based on the Dragon Heart.”

“Yeah. Its body length exceeds 100 meters.”

“That’s Leviathan for you. She has been waging war for a year… no, wait.”

The war has been ‘ongoing’ for a year, meaning the war ‘started’ a year ago, which means Leviathan first revealed herself a year ago.

“She might have been summoned even earlier than we think. Even if she was just a small shark back then, considering Leviathan’s abilities and survival instinct, she would have quickly risen to the position of an apex predator.”

“Right. When she first attacked Belselphia, she had already formed her own massive army.”

“Did she not catch on?”

“Well, the sea is much larger than you might imagine…?”

“I get the general idea.”

Leviathan’s competency.

Celcius’s incompetence… or rather, her laid-back demeanor.

It can’t really be blamed on Celcius.

As she said, the sea is vast, and Leviathan must have been operating like an ordinary wild animal in places Celcius couldn’t keep track of, steadily building her power.

From the perspective of the weak, she devoured the thoroughly weak.

Gradually, she gobbled up stronger beings for power.

If a slightly strong one showed up, she would crush that one with strength and turn it into her subordinate.

And at the moment her truly massive army was formed, she threw down the gauntlet to Celcius, the ruler of the sea.

“The ruler of the sea in the Demon World has thrown down a challenge to the ruler of the sea in the Intermediate Realm.”

“Well, that’s one way to put it. Phew, hearing that makes me feel a bit relieved. If that sea dragon wasn’t the ruler of the Demon World’s sea, I would have seriously cried.”

It seems Leviathan being the strongest in the Demon World gives her some relief.

That much must have secretly caused her a lot of mental distress.

“Well, still, no one here can defeat me in this world!”

“That’s true.”

Swoooosh.

Within the water mist, the body of the giant sea dragon, over 100 meters long, was instantly swept away along with the marine monsters.

That blow appeared to be a hundred times, no, a thousand times more powerful than when the Holy Sword Hero Liriez swept away the Narag Poison Bugs with the Holy Water Sword.

The Holy Sword draws upon Water Mana.

It’s only natural that Celcius, being Water Mana itself, would show such strength.

As a Water Spirit, she didn’t need to hide her power, and Celcius magnificently subdued Leviathan.

“But you can’t go after Leviathan to eliminate her.”

“……. ”

Celcius can only exert her power within this area, Belselphia.

To be precise, the driving force behind her ability to act with such will and effectively engage lies in Belselphia; hence, she can influence the world as a part of nature.

“Celcius, are you here?”

“Yes.”

Celcius is here.

Correction.

The ‘Spirit Device’ Celcius is here.

A massive city called Belselphia was created based on the Spirit Device.

No, if we trace back to the source…

“Here, this was originally the hangar of the Spirit Device, right?”

“Yes. Gradually expanded the space. Now it’s not just a hangar but a massive city.”

“Is that so….”

Should I have brought Liriez with me?

If she knew where the Spirit Device she summoned was located, she’d surely be very happy—

“…Wait. Was it that a Hero using Ascalon was needed?”

“That’s right. The Water Hero awakened the ability to use the Spirit Device, but the power she can use here has significantly diminished.”

“……. ”

“Fortunately, last time, the timing was just right, so the enemy didn’t invade. But once Leviathan realizes the Spirit Device has been summoned outside, she’ll definitely attempt to attack immediately.”

“……. ”

The absence of the Spirit Device triggered a crisis for Belselphia.

In other words.

The culprit is…

…me?

*

At that moment.

In the darkness, something began to sparkle.

In the lightless abyss, a being swimming through the sea with black eyes dazzlingly emitted the ‘source of power’ far ahead, opening its mouth wide.

[My Demon Lord. We are prepared to sortie. Ready to launch another offensive.]

[No.]

The giant sea dragon firmly shook its head to the words of the octopus, which reached up to 10 meters in length.

[For now, let’s observe the situation a bit longer. Their power hasn’t weakened yet.]

[But you are the Demon Lord who said we should push with numbers, aren’t you?]

[The situation has changed. While only briefly, there was a moment when the enemy’s power in their territory weakened.]

Leviathan gently opened her mouth.

[The currents have surely shifted. It felt like something important was being lost. It probably isn’t temporary.]

[But….]

[Trust my instincts. The only one who can defeat me in the sea is one.]

[One? Who is that?]

[Bel.]

Leviathan twisted her mouth into a fierce grin.

[Only the Demon Lord of Sloth can fight me with full power in the sea.]

[Are you referring to the Great Demon Lord Bel Phegor from 500 years ago?]

[Yes.]

[Oh, ohh…!!]

The Kraken flailed its tentacles, becoming overly excited.

[The legendary Demon Lord! That person had been living in the Demon World since leaving the Intermediate Realm!]

[Yes. If it’s not that fellow, we’re guaranteed to win.]

The sharp teeth of the sea dragon were precisely aimed at Belselphia.

[Something is reacting…. It has arrived.]

Above Belselphia, a blue light began to shine.

[Hiiik…?! The light of the Crescent Moon Goddess…?!]

[That’s not it. That is… the power of the Holy Sword.]

Leviathan opened her mouth wide as the scales extending out to the sides expanded fully.

[Prepare. To announce the true ruler of the sea to the world.]

*

At that moment.

In the center of the Order of the Crescent Moon Goddess.

“Under the membership of Pope Lucid, I will now prove the faith of Holy Knight Commander Liriez Cesarcross.”

The middle-aged man with blonde hair declared to the priests gathered in a circular formation.

“Our faith is directed towards the Crescent Moon Goddess. All forms of strange powers and deities other than her are heretical and taboo. However, let us pray for this unfortunate lamb who claims to have broken the taboo.”

“Pope Your Holiness…!”

“The Water Hero, who wields the Holy Water Sword, has unraveled the sealed history, and the fact that she is none other than our Holy Knight Commander of the Order of the Crescent Moon Goddess surely embodies the will of the Crescent Moon Goddess.”

Pope Lucid opened his arms with a benevolent smile.

“Commander Liriez. The traces of the sealed history you have awakened undoubtedly follow the guidance of the Crescent Moon Goddess. Am I correct?”

“…That’s correct.”

Liriez replied to the Pope’s words with a heavy face.

“Then, I will now ask you. Can you reproduce the miracle the Goddess has shown you here?”

“…Of course.”

Liriez unseal the Holy Sword before everyone’s eyes and thrust it into the ground as she spoke.

“…O Aura, Celcius.”

A moment later.

A blue stream of water began to rise, centered around Liriez.

 

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