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I’m going down! To the ocean floor!

‘It’s been a really long time since I came down here.’

To say one thing, I’ve been to this underwater city before.

Specifically, I visited here as part of a Hero Party, and at that time, I came along with a hero wielding the Holy Water Sword.

– Hero, you’re going to release the power of the Holy Sword to defeat the Demon King…?

– Yes, that’s right.

– I’m right behind you, you know?

– Oh.

And thanks to Celcius, my identity as the one infiltrating the Hero Party was exposed.

The Spirit Device was freed, and I nearly died fighting, but fortunately, the hero defeated the enemy, and I managed to retrieve the Holy Water Sword.

– …I’m sorry.

– Let’s do better. Okay?

– I’m really sorry.

In some ways, it could also be said to be my fault.

I didn’t tell Celcius in advance not to acknowledge me since I was infiltrating the Hero Party.

If there’s no fault on Celcius’s part, then it’s just that she blurted out my identity without realizing it, but honestly, I was grateful for her remaining neutral.

If the Water Spirit got angry and turned all drinking water into poison, the Demon King’s Army would be decimated.

Of course, if she goes against the laws of nature, Celcius would suffer just as much, but it’s entirely possible for nature spirits to plunge the world into destruction out of anger.

Fortunately, they had no intention of doing so.

‘She’s a great kid, except for her lack of awareness.’

This is exactly why I felt the urge to deal with Celcius as soon as I met her.

What if she noticed me, who’s inhabiting the body of this girl?

– I am Arthur Lucius, the hero wielding the Holy Wind Sword to defeat the Great Demon Lord Bel Phegor! And this is the Sorceress of Crimson Lotus, Bel, who awakened me!

– Bel Phegor? This is Bel Phegor? Hey, nice to meet you. You’re doing the same thing you did 500 years ago!

– ……Wind!!

Instantly dead.

I fervently wished that it wouldn’t come to that as I descended to the ocean floor.

‘At least I can talk before my party does.’

I had already succeeded in establishing ‘connection’ with Celcius by boarding the Spirit Device.

Although she probably still thinks I’m just a mana-rich lich magician, if we make eye contact, she’ll surely notice my presence hidden inside.

– Right now, I’m infiltrating the Hero Party! No spoilers! I need to get rid of the remnants of the Demon King’s Army, so if my identity is revealed, the world is doomed?!

I just need to rapidly convey my intentions through our mana connection as soon as we meet.

Even if she’s someone lacking awareness, we shared old bonds from 500 years ago; at least she’d keep her conscience intact.

What if she doesn’t?

What if she holds some grudge against me and tries to expose my true self?

“…….”

Then I’ll kill her.

Ex-girlfriend or not, even if she claims she unintentionally screwed me over multiple times 500 years ago, if she does it again, I will definitely kill her.

I cannot kill an existence that is nature itself, but a conscious being known as ‘Celcius’ is entirely dispensable.

It’s somewhat similar to turning a rational human who dies into an undying creature that has lost its senses.

‘If I hadn’t met Liriez and received the Holy Sword’s code, it wouldn’t have been possible.’

Meeting with Liriez was truly destiny.

If I hadn’t made contact with the Holy Water Sword and acquired the sub-master privileges, I wouldn’t have even suggested coming to the north of this continent, no matter what Ascalon was babbling about.

So.

All preparations are complete.

Now it’s just a matter of contact.

Roll, roll.

Lucius’s barrier rolled along the sea floor like a ball.

“Ugh….”

Goooorrrrr.

It might be because we had gone deeper, but one by one, the deep-sea creatures brushed past us, causing the other party members to swallow their saliva nervously.

“Don’t be scared. They may look like that, but as long as the barrier from the Holy Sword is up, we’re safe.”

“What if the barrier wasn’t there?”

“Then they would try to eat us right away.”

“Eek…!”

I might be somewhat used to those ugly creatures, but it seemed that the other three ladies were genuinely disgusted.

“They look even weirder than what I saw in books.”

“Seriously. But they are a bit strange.”

“What do you mean?”

“I feel like they are sharper than what I saw 500 years ago. Back then, everything was a bit roundish.”

Goooorrrrr.

The enormous streamlined creature that passed by us was undoubtedly a whale.

Its massive body likely exceeded 30 meters, and I suspected it could be a humpback whale filled with mana in its heart, circling around us and smacking its lips.

“Smart creatures. They learned from those that were already cut by the barrier.”

Actually.

We had already been attacked several times.

As soon as the barrier sphere pierced a hole and entered the ocean floor, we were assaulted by various deep-sea monsters, including man-eating sharks.

Naturally, the barrier was made of golden storms and icy winds.

The deep sea quickly turned into a crimson sea of blood, and we had no choice but to watch countless deep-sea monsters get shredded by Ascalon’s icy gust until we reached the bottom.

Thus, we were currently being pursued by two major groups.

One was a scavenger group, eager to munch on the corpses of the foolish creatures that touched us out of curiosity and ended up getting torn in half.

The other group appeared to be hunters, keeping their distance to observe until the barrier ended.

The humpback whale belonged to the latter group.

“Master, that whale is opening and closing its mouth toward us.”

“Leave it alone. The moment it eats something, its palate and tongue will get shredded like the undead. No reason to stop a whale that’s becoming its own sushi.”

And also, I’ll collect some magic stones.

“…But they all sure look sharp.”

What’s going on here?

Did they all evolve to have rough bodies to survive in harsh conditions over the past 500 years?

It’s typical for deep-sea fish to have supple and smooth bodies, generally having that slimy texture like slimes.

But those guys had sharp and pointed forms that resembled arrowheads.

Just like…

“……They remind me of the Demon World’s fish.”

“The Demon World fish?”

“Marine creatures that changed their entire bodies into weapons to survive harsh environments in the Demon World. For instance….”

Just then, a suitable example passed right in front of me.

“They make their fins like razor blades to slice their enemies. Their scales are not rounded but have pointy features like a special plate armor.”

“Definitely different from fish caught in rivers.”

“Right? This definitely feels….”

Wait a minute.

“…….”

I had a bad feeling about this.

Something was thumping in my chest, and I was dizzy as one of the magic stones I kept in my pocket glimmered purple.

Right now, is it agreeing with what I’m thinking?

Though it has no consciousness and is sleeping along with my soul, does it feel the same way?

“…If it’s not for the power of the Holy Sword, I would have really been dead. It seems something significant happened here over the past 500 years.”

I pointed to the front towards the coral forest.

“Let’s head in there. As we scrape the bottom, we’re bound to find a place that feels odd.”

“Should we continue forward then?”

“Yeah. Think of it as cleaning and sweep through the inside of the coral forest.”

Although my party tilted their heads at my orders, Lucius quietly continued to move the barrier.

And then.

Kagagag.

A sound like scraping metal echoed as Lucius immediately stopped advancing the barrier.

“I found it.”

“What did you find?”

“An entrance.”

In the center of the coral forest was an entrance.

“Lucius, instead of scraping the ground, can you make a cushion-like platform here so we can sit around?”

“Is this how you want it?”

Wiggle wiggle.

The shape of the barrier instantly changed, transforming into a square prism.

“…I’ll control this part of the barrier.”

After asking for Lucius’s understanding, I precisely deactivated the barrier just over the section of the steel plate hidden under the sand.

Water didn’t seep in, nor did the air suddenly rush out.

Swish, swish.

[CE-93]

As I pushed aside the sand, a peculiar-patterned steel plate emerged.

It was wide enough for two people to lie down comfortably.

“Here it is. The underwater city. We can enter through here.”

“…Isn’t it blocked?”

“That’s why we have to open it now.”

Opening it is simple.

Knock, knock, knock.

“Is anyone there?”

Since it’s an outsider visiting, it’s only natural to knock.

“Could you please respond if someone’s inside? If you don’t open in three seconds, I’ll break the door down and come in? We’re a Hero Party?”

Since I have the Holy Sword, I can speak confidently.

“Master, if there are Demon King’s Army members inside, they probably won’t open up.”

“Then we have a justification. We can force our way in.”

Personally, I hope they’d just break down the door and let me in.

Because I want to storm into my ex-girlfriend’s home.

[……An outsider, is it?]

A deep male voice echoed from the steel plate.

It wasn’t coming directly from beneath the plate, but rather through a voice amplifier attached next to it.

[It’s been 500 years since a Hero Party came here.]

The party I had visited long ago.

[At the same time, it’s been nearly 500 years since earthlings descended into the abyss.]

“If you don’t mind, I’d like to speak with the Water Spirit. I am the guide of this party, ‘Sorceress of Crimson Lotus’ Bel.”

[…That name rings a bell.]

Oh.

It’s someone who knows me.

[Are you really the Sorceress of Crimson Lotus?]

“Yes. After the Demon King was defeated, I was sealed away in preparation for the day the Demon King returns.”

[…I see.]

He knows the Sorceress of Crimson Lotus well.

[Is the one beside you a hero? A male?]

“Yes. He’s the hero wielding the Holy Wind Sword, Arthur Lucius.”

[…….]

The man was silent for a moment.

I felt anxious, worrying if he might realize I’m not truly Bel, but my concerns turned out to be useless.

[Let me be clear, I personally dislike the Sorceress of Crimson Lotus and the Holy Wind Sword for personal reasons.]

Creeeaaak.

The door opened.

Below was a vertical passage that went straight down, and the man I guessed had been speaking with us was looking up at us.

“But… It has been a while since I met an earthling who can communicate properly.”

“……!!”

“Master? Do you know him? I can hardly see….”

“No.”

I don’t know him.

It’s just that.

“…An elf with a bald head and an aquarium on his head.”

The reunion with an inhabitant of the underwater city after 500 years was sheer shock.

 

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