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Tensei Shitara Slime Datta Ken (WN)

Chapter 78 – Demon Lords · Nov 11, 2026

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Chapter List (417)

Page number / 9

51 Chapter 49 – Hurricane Milim 2026-11-11
52 Chapter 50 – Frontier Garrison 2026-11-11
53 Chapter 51 – To the Human City 2026-11-11
54 Chapter 52 – Journey 2026-11-11
55 Chapter 53 – Freedom Association 2026-11-11
56 Chapter 54 – Business ~ The Start of a Trade 2026-11-11
57 Chapter 55 – Adventurer Registration 2026-11-11
58 Chapter 56 – Ingrasia Kingdom 2026-11-11
59 Chapter 57 – To Learn Magic 2026-11-11
60 Chapter 58 – The Summoned ~ those who are called heroes ~ 2026-11-11
61 Chapter 59 – The Church Moved 2026-11-11
62 Chapter 60 – A bit sudden, but let’s have a test 2026-11-11
63 Chapter 61 – The First Dungeon Conquest 2026-11-11
64 Chapter 62 – A Spirit is… 2026-11-11
65 Chapter 63 – Children and Spirits 2026-11-11
66 Chapter 64 – Last Days in the Royal Capital 2026-11-11
67 Chapter 65 – The Prelude to Disaster 2026-11-11
68 Chapter 66 – Chance Meeting 2026-11-11
69 Chapter 67 – Forest Assailants 2026-11-11
70 Chapter 68 – Soul and Hope 2026-11-11
71 Chapter 69 – Birth of Demon Lord 2026-11-11
72 Chapter 70 – Harvest Festival 2026-11-11
73 Chapter 71 – I, the one who had sprouted 2026-11-11
74 Chapter 72 – Upon Awakening 2026-11-11
75 Chapter 73 – The Freed One 2026-11-11
76 Chapter 74 – Veldora 2026-11-11
77 Chapter 75 – Conference 2026-11-11
78 Chapter 76 – Conference – Main act 2026-11-11
79 Chapter 77 – Ramiris’ Report 2026-11-11
80 Chapter 78 – Demon Lords 2026-11-11
81 Chapter 79 – Dino and Dagruel 2026-11-11
82 Chapter 80 – The Incident before the Banquet 2026-11-11
83 Chapter 81 – At the Banquet 2026-11-11
84 Chapter 82 – Equality in Death 2026-11-11
85 Chapter 83 – Eight-star demon lords 2026-11-11
86 Chapter 84 – The Downfall of Falmas Kingdom 2026-11-11
87 Chapter 85 – The words that reached 2026-11-11
88 Chapter 86 – Those who move in the dark 2026-11-11
89 Chapter 87 – The Holy City 2026-11-11
90 Chapter 88 – Towards the second encounter 2026-11-11
91 Chapter 89 – Different Plans 2026-11-11
92 Chapter 90 – VS. Holy Knights Part 1 2026-11-11
93 Chapter 91 – VS. Holy Knights Part 2 2026-11-11
94 Chapter 92 – VS. Holy Knights Part 3 2026-11-11
95 Chapter 93 – VS. Holy Knights Part 4 2026-11-11
96 Chapter 94 – Mastermind 2026-11-11
97 Chapter 95 – Complete Victory 2026-11-11
98 Chapter 96 – Chance to Speak 2026-11-11
99 Chapter 97 – Compensation and future relations! 2026-11-11
100 Chapter 98 – Letter of Invitation 2026-11-11

Translator’s Corner (cast: Clown and Pierrot)

Pierrot: Clown! Any new memories?

Clown: No. I’m taking these pills the doctor gave me to forget.

Pierrot: Why would you do that? Are you an idiot?!

Clown: But… they seem like painful memories, wouldn’t I want to forget them?

Pierrot: Let me ask you this… let’s say you had ten thousand yen in your wallet.

Clown: Okay?

Pierrot: Then, you wanted to test what would happen if you submerged it into acid. Of course, the money dissolved.

Clown: Oh no!

Pierrot: Now, that’s a painful memory, but would you want to forget it?

Clown: …

Pierrot: You wouldn’t, right? Otherwise you would just do it again and go bankrupt.

Clown: Is that where the rent money went?

Pierrot: …

Clown: …

Pierrot: Maybe…

Birth of a Demon Lord Arc

078. Demon Lords

Demon Lord Clayman was in an unprecedented state of panic.

The humans were guided into action as planned.

The result was supposed to be a bloodbath of a battle, filled with suffering and tragedy which his soul would reap and relish.

However, the battle was concluded in an instant and all the souls were absorbed by a third-party.

He couldn’t believe it, but the recent report confirmed it.

This was a stage prepared by that honorable individual.

A fight between monsters and humans that would lead Clayman into awakening as a True Demon Lord.

Thus, he hardly cared for his subordinate Myulan, and planned to dispose of her soon after.

But he now lost connection with her. Moreover, her curse had been released and she was now free.

This fact only added to his anxiety.

But only that much was hardly a matter for concern.

Fortunately, he still has the strongest trump card known as Milim.

Thus, he had forced Frey to schedule a Subjugation Council–Walpurgis Banquet.

As it had Milim’s, Frey’s, and his signature on it, it was quickly approved; there he wishes to call for an extermination of the presumptuous Slime who dared to call itself a demon lord and its city.

Because marching his troops in the direction of human cities is strictly forbidden.

At this Subjugation Council, he will first secure dominion over the other demon lords and then obtain the rights to invade the Monster Country, Tempest.

While trampling every country along the way, of course.

As for the high ranking devils of that country, he’ll have Milim crush them.

Were it a few days ago, he could have crushed them all himself, but due to their master’s evolution, they all became devils and acquired greater power.

At this point, Clayman lamented the fact that the first plan had failed.

Well, he only had to rule over whoever remained after Milim was done with them.

But…

Suddenly the shut-in demon lord Ramiris, requested that Slime Rimuru would be granted permission to attend.

And strangely, he was given permission really quickly.

Clayman tried to veto the request, of course, but, as if it was the most natural thing in the world, three other demon lords accepted it.

Which caused all of Clayman’s plans to fall apart.

The Walpurgis Banquet that he so painstakingly gathered now was home to his enemies.

Nor could he run away from it.

If the slime himself came, even if Clayman called for a subjugation, the battle would occur at the Banquet.

“What to do? What should I do?”

Clayman desperately sought a way out of this predicament.

This desperation was observed by Frey who was smirking.

What an unsightly man.

Things were proceeding faster than she expected.

Though she had not predicted this outcome, it was nonetheless to her favor.

She looked at the expressionless Milim standing across from her,

At her cute face–completely void of any emotion,

At her eyes, which suddenly looked elsewhere. At Frey.

Frey nodded.

(Yes, that’s right. I understand, Milim)

She responded in her mind, with a profound smile.

And…

(Clayman, you will live not much longer)

Frey was secretly confirming theupcoming plan.

＊　＊　＊

In an unknown land, in the innermost burial chamber,

In front of a coffin wrought of ice which sealed a beautiful naked girl with flowing black hair,

Stood a being, themselves nude, beholding the coffin with a suspicious gaze.

(Ah, how beautiful. Ah…)

Observing and adoring the coffin girl was this being’s secret pastime.

A silver haired cute girl.

Her heterochromatic eyes glistened with a bizarre red and blue light.

This, among her many strikingly beautiful features, was the most prominent one.

But perhaps what garnered the most attention…

Were two pure teeth that peaked from within her small lips.

When her small lips parted, they revealed a set of pure white fangs.

She was the ruler of the night, Queen of Nightmares.

Demon Lord Ruminas Valentine.

Even she, a vampire possessing the immense power of a demon lord, could not break the ice coffin.

As it was not actually made of ice but was a pure lump of holy spirit energy.

So even touching the coffin would leave burn like marks on her body.

However…

Without any regard to this, she clung to the ice coffin.

An invitation to attend Walpurgis Banquet reached this girl.

Unfortunately, many beings of comparable power would attend.

Thus, she currently lacked the power to make them her enemies.

Though this vexed her to no end, there was naught she could do.

(Wait for me…)

She whispered the name of the adored girl, and left the chamber.

And gathering a vast amount of magical energy, she submerged the chamber in darkness.

＊　＊　＊

Two men were in the middle of a conversation.

The first was a large, sturdy man clearly known for his height.

The other was slovenly lying down, without a hint of dignity.

However, as this was his usual appearance, the former paid it no mind.

「So, how long will you be staying here?

Will you set off on another journey after the Walpurgis Banquet?」

「No clue~. What a pain. Nothing excites me anymore~」

To the large man’s question, he replied without any motivation.

But whichever…

「But surely you have no choice but to participate in Walpurgis Banquet?

So you might as well start considering what you will do afterwards」

The large man concluded.

And looked at the vast sky above as if enjoying the view.

Minutes passed silently between them,

「Hey, Dagrule, do your sons feel like becoming a demon lord?

I can take them under my care, if you’d like?」

The delicate man said as if he just remembered this idea.

The large man… no, Dagrule closed his eyes for a minute and was deep in thought.

One of the Giants, this demon lord is often referred to as “Continent’s Wrath”.

Normally a gentle man he finds the title unpleasant, but when angered he truly can’t stop his hand.

His power greatly increases when angered so he’s a demon lord treated with utmost care.

And his most closest friend, the delicate man, has never once angered him.

To the delicate man’s words,

「Nah, they resemble me when I was young.

They are rash, look down on everything, and believe that a being stronger than them does not exist.

They would look down even on you, Dino」

He replied.

The delicate man’s name is Dino. A man of unknown race with an appearance no different than a human.

But, he possess magical energy of such quantity that no human could possibly match.

Though he is a handsome man, his sleepy gaze ruins his appeal.

But he too is a demon lord. Called “The Wandering King” or “King of the Sleeping Forest”.

Even now, he has left his home and is in the middle of a journey.

And having used up all of his strength during the journey, he ended up in the care of his best friend Dagrule.

In response to Dagrule’s words,

「Ah, I don’t mind. My worth wouldn’t diminish from such a thing.

But if they are so impudent, how about you bring them over?

You have three sons, so I can bring one of them in my name?」

He said.

Of course, he meant to take them to the Demon Lords’ Walpurgis Banquet.

Dagruel thought a bit on these words.

And,

「Can I ask this of you? If they act foolish and die without coming to know true power, then that’s that.

So showing them true strength would be an excellent lesson」

He nodded.

His three sons. Like him, they are a violent bunch.

Agreeing to bring them, they continued the conversation with this in mind.

However, bringing them there is much like starting a fire next to gun powder, but these two failed to recognize it as such.

After all, both of them were particularly bad at careful planning.

＊　＊　＊

In a land covered by ice where fierce blizzards reigned,

Proudly stood a tall castle.

Its vicinity was covered in a barrier of ice, with temperatures of minus 120° Celsius such that nothing could live there.

And yet a beautiful castle adorned the land.

Its presence testified to an unimaginable amounts of magical energy–truly a castle of the highest demon.

The Castle was named “Palace of White Ice”.

And it was ruled by Demon Lord Guy Crimson.

There was a being leisurely walking though the castle.

Platinum Gold long hair, blue narrow eyes. A well defined face.

Skin so white that it was almost transparent.

He was so beautiful that he was surely mistaken for a woman.

Demon Lord Leon Cromwell. The one called the Blond Demon.

He proceeded through the halls as if he owned them.

Ahead of him was a door with beautiful carved decorations. It led to the audience chamber of the lord of the castle.

Leon’s purpose in attending was the lord of the castle, demon Lord Guy Crimson.

Leon stood in front of the door, and the two large attendant demons opened it.

And,

「Demon Lord Leon Cromwell-sama has arrived!」

A female-like demon announced the coming of Leon from above.

On the inside, many powerful Greater Demons stood on the sides.

Each was a named demon so greatly surpassed the power of a normal greater demon.

There were over 200 of them in total.

Named Greater Demons differ from normal ones as they possess a corporeal body in this world.

So each could easily rival a high ranking devil.

In other words, the room had 200 beings of a rank easily surpassing A.

But that’s not all…

At the end of the room, before the throne of Demon Lord Guy Crimson stood six demons of terrifying power.

They were Named Arch demons.

They battle power was surpassed any devil. These were pseudo-demon lord level demons.

But…

These six demon generals prevented any excessive word from going unpunished.

Ruling over all of these as Demon Lord Guy Crimson’s left and right hand were two demons.

Having become “Demon Officer” these two women serve as the Demon Lord’s spokesmen.

They possess power that rivals that a demon lord.

“Demon Officer” Mizari and “Demon Officer” Hirari.

Leon proceeded further in and stood right below the throne.

And that’s where Mizari and Hirari kneeled, and

「「Leon-sama, it has been a long time」」

At the same time they greeted Leon with a beautiful voice.

And at the same moment, the Lord of the Castle stood up from his throne.

Only the two demon lords now had the right to move within the room.

「It’s been a while, my friend Leon. Have you been in good health?

Let me thank you for coming over when I called you!」

A beautiful, projecting voice, deep crimson eyes which overshadowed the beauty of stars, hair flowing like fire, with a deeper red than the color of blood.

Same height as Leon.

Where Leon is as beautiful as a woman, Guy’s beauty was more neutral.

He could be called a woman or man; a bizarre physique.

While calling out to him, he stood up from the throne and walked up to Leon.

And after shaking Leon’s hand, he gave him a hug.

And without any hesitation, he placed his hand on Leon’s face and kissed him.

Leon pulled away with a scowl,

「Stop it. I’m not interested in dating men. How many times have I told you this already?」

He told him, treating it as a bother.

「A haha. Heartless as always.

You know, if you ask, I’ll become a woman?

Ah whatever, let’s move to a different room」

He said, and without waiting started walking.

This happened every time.

He was exposing a lot of skin while dressing in a kimono in this frigid land.

Perhaps remembering the taste of Leon’s lips, a lewd smile formed on his bewitching face.

And he started to work his tongue around his red lips….

That motion had a suspciously bewitching effect to it.

Being androgynous, he could become a man or a woman at will.

He… or perhaps she is Demon Lord Guy Crimson.

The Lord of the Castle and the oldest Demon Lord.

Called the Lord of Darkness, he has forever ruled over this frozen continent.

Guy proceeded onward showing Leon the way.

Leon followed without any sign of worry.

Until both of them left the audience chamber, not a single being had moved.

As that would have been an unforgivable act.

With their heads bowed low, they waited until their master and guest had left.

Having confirmed their departure, Mizari and Hirari stood up.

And,

「Disperse!」

They ordered their subordinates.

As for them, they began to make tea for the guest.

Among the highest beings of the castle, the job of these “Demon Officials” was nothing more than to care for Demon Lord Guy Crimson.

And that job had the highest priority within the castle.

So as to not earn the displeasure of their lord, they quickly got to work…

Leon followed Guy to the Ice Terrace on the highest floor.

Even though it opens up to the outside, snow is not permitted entry.

The environment is optimized for life.

In the first place, Guy is not affected by the environment. In other words, the room is made for Leon’s enjoyment.

Though Guy normally looks down on any stranger, for his friends he spends both effort or expense.

“Just like always,” Leon thought, taking a seat.

Though the chair he sat on was made of ice, he did not feel the cold.

That too, was the routine.

「So? Why have you called me?」

Forcefully flopping into the chair, Leon asked.

When did they have time to prepare it is uncertain, but Hirari brought in tea.

Mizari silently stood at the entrance to the terrace.

That too she did without anybody noticing.

They stood as to not intrude upon Guy’s conversation, and so, did not address Leon.

The girls were nothing more than tools, after all.

Since they had nothing to do with this conversation, they were not permitted to even show an expression unless ordered to do so.

So any motion that was not specifically ordered of them would lead to certain and quick death.

In fact, even if Leon attacked Guy, they would not move.

Guy was their supreme master, so worrying over his health was disrespectful.

Thus, ignoring their existence, they continued their discussion.

「Ah. You do know about the upcoming Walpurgis Banquet?

I was thinking that if you couldn’t attend this time, I’d forcefully have you attend」

「Huh? You know I hate these gatherings?

But I was planning on attending」

「Oh? Good, then. I had planned on having you make a clone and attend that way.

I could have you embrace me then」

「I don’t take men for partners. Even among women I only go for the one I desire.

For me to embrace you would be equivalent to some prize, wouldn’t it?」

「What’s with that? Tell me that earlier… If you wish for it, I’ll become a woman for you.

Whatever. So?

Why did you decide to participate this time?」

「Ah…」

Leon made a brief pause, but then continued talking.

「This time the banquet is hosted by Clayman. Small fry.

I’m curious why Milim is supporting him.

And Karion’s death is also suspicious.

At first it was because Clayman wanted to spur us on a subjugation, but then Ramiris requested that the party in question attends.

In other words, it’s all connected.

So I feel the need to see, this new Demon Lord “Rimuru”」

「Oh. So you believe Rimuru has the qualifications to be a demon lord, huh?

How amusing, I thought the same thing.

As for Milim, she’s probably just playing around. No use trying to figure out what she’s thinking.

The wise one in me cannot understand fools. That might be a weakness.

So it’s fine to ignore the opinion of someone like Clayman; Ramiris’ opinion, on the other hand, seems promising.

If she found someone interesting, maybe even I will enjoy myself.」

「… Ramiris, huh? I’m no good with her. From the very moment we met.

I had thought to go and kill her a few times…

But since she mentioned it, I might as well go and see」

「A hahaha. Don’t. If you kill Ramiris, I’ll be your enemy」

「Right. And I don’t want to die yet. If you come at me, I see no chances for victory」

「Hmm? Not at all. You have a one in a million chance of killing me, you know?」

「Then that’s no good. I’m only interested in fights that I can win」

「Stop with the humility. There’s few people who can even hurt me.

Having a chance to kill me means that you’re strong. Have some confidence」

「Hmph. I am confident. Against anyone other than you, that is.」

That’s where their conversation stopped,

And without a moment passing,

「Ara ara. Has your conversation finished?

Leon-sama, I extend my humblest welcome」

A voice like ice.

And it came from a beautiful white haired girl.

Pure white skin, with cold and bewitching Blue Diamond colored eyes.

And bright white lips.

A girl walking around without Guy’s permission.

But she did not need his permission. In other words, she was their equal.

“Ice Empress” she was called, but is more known by her name “Ice Dragon Velzado”.

She is one of the four dragons, and Demon Lord Guy Crimson’s first subordinate.

Though rather than calling her a subordinate, it may be more appropriate to call her a partner.

An existence far different than the tools.

「My oh my, Velzatto. Beautiful as always」

「Ara? Even if it’s only flattery, your words have made me happy」

A brief polite exchange.

That revealed none of their real feelings.

「Hmph. You guys are on bad terms as always」

Guy as well was vexed at their animosity.

Normally, this would have led to an unpleasant exchange…

But this time, Velzatto changed the topic.

「Right, right. My “brother” has awakened」

She suddenly declared.

「Awakened? The sealed “Storm Dragon Valdora”?

I know that he was sealed, but didn’t they say he had been erased?」

「Yes. He had quieted down before disappearing, so I thought to help him out…

Being erased is pitiful, you know.

He was trapped in an isolated space made by the hero that could not be influenced by the outside.

Many beings have lost their lives swallowed by such barrier」

「Oh… interesting.

In that case, who could have dispelled this hero’s seal?

Unique skill “Eternal Prison”, other than by other heroes, could not be dispelled by a normal skill.

I have the … skill, and perhaps by your … skill.

Well, we had planned to release him sooner or later.

But considering that he has not rampaged since being released, does that mean he has weakened?」

「Yes. He has. The response I am getting from him is strangely weak.

But still, not rampaging is quite unlike him.

His very being is made around the concept of violence, after all.」

「Well, in any case, I have no desire to fight Veldora.

If you want to make him yours, do as you wish.

Anyways, let’s meet at the Walpurgis Banquet」

「You are leaving already?」

「Yeah. That’s all you wanted from me, right?」

「Ah, wait a second. No need to rush.

By the way, have you succeeded with the “Special Summoning” yet?」

「… Not yet.

Frankly, I don’t care much for new demon lords or what-not.

It’s just, according to my sources, this one might be messing with my summoning tests」

「Oh? The one named Rimuru?」

「Yeah. So I want to at least see him once.

But I’ll be ignoring Ramiris, just so you know…」

「Just curious, but who’s this informant?」

「No idea. Magic Energy is a important factor when summoning “World Travelers”.

When I summon, since I try to narrow down the criteria as much as possible, the interval becomes much longer.

At the present, I can only summon one being once every sixty six years.

But since I need to narrow down the criteria even more, my next summoning attempt will be in ninety-nine years.

This informant is trying out summoning in my place during this time」

「How timid of you」

「I’ve failed many times, you see. Even after obtaining “Luck Blessing” from Ramiris, I couldn’t succeed」

「Is this matter that important?」

「Yeah… To me, it’s more important than anything in the world」

「I see. In that case, I won’t say anything.

But about this assistant… is he trustworthy?」

「Trust? No way. But he does have some use」

「I see. I know I don’t need to say this, but do be careful」

「That’s not like you, Guy. But, I’ll accept the warning.

Thanks. Now then, let’s meet at Walpurgis Banquet」

Leaving these words, Leon left,

Leaving only a ball of light behind due to Spatial Movement magic.

Seeing this,

「What an impatient man. Well, that’s just like him」

Guy muttered while grimacing.

「But, he has created a dangerous opening.

This unknown “assistant”… should I crush him?」

Velzatto asked with a cold voice,

「Don’t. Unnecessary actions will only earn Leon’s displeasure.

I have no desire to be hated by a friend」

Guy answered, unworried.

To Guy, Leon was a trustworthy friend so these words were born out of familiarity with his personality.

Moreover, he simply knew how powerful Leon’s abilities were.

「When he comes asking, we’ll help him」

「Understood」

And that conversation ended.

Guy confirmed that his stay-at-home friend will be attending. Even though he was called out without a care for his needs, Leon seemed not to mind.

Guy as well had ignored the summons a few times, but could not remember why.

Thus, after a long time, all the demon lords will gather.

「This banquet seems promising, will you come?」

「Will I… No, I won’t.

I have no interest in demon lords」

「Is that so? Oh well. In that case, I leave the house-sitting to you」

「Yes. I’ll make the necessary preparations」

Velzatto left after uttering these words.

Guy, left behind, observed the aura of the icy continent, while thinking about the upcoming Walpurgis Banquet.

A crafty demon lord prowling around.

A small fry, signifying the weakening demon lords.

A shut in friend who finally took action–Guy found this point interesting.

And, the birth of a new demon lord.

How amusing. He had felt the loud beating of his heart for the first time in many hundreds of years.

The last battle was between weaklings.

Perhaps he could look forward to the upcoming one.

With that thought, he started thinking about the hero.

When was the last time he had felt one…

The one that invaded Leon’s castle was also a hero.

Leon ran away without fighting, claiming that the hero was strangely strong.

It wouldn’t be strange for a human to die of old age by now, but Ramiris claimed that this hero was “special”.

So it wouldn’t be strange if it could extend its lifespan.

Nor were its movements regular, appearing only before powerful individuals.

Guy had never been able to meet the hero, but would have wanted to try fighting it once.

This time’s fight might be grand.

It may not involve only monsters, but have the saints and the humans mixed in, resulting in a great calamity.

So perhaps even a hero will appear.

At this point, Guy had completely forgotten about the new demon lord.

To him, demon lords were a trifling existence…

He desired to meet a hero. That thought brought a smile to his face.

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