The Hero’s Mentor is a Demon (King) Witch

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Beelzebub.

He is one of the seven Demon Kings that rule the Demon World, including me, Belphegor.

Appetite, gluttony, devouring.

He is a Demon King related to everything concerning eating (食), and he is a monster of indulgence that devours everything into his belly.

Is he strong?

If you ask that, I could say he is the weakest among the Demon Kings.

Demon Races love to fight over their hierarchy, but having fought directly with heroes, I could estimate without battling the Demon Kings.

At the top are three members of the deep and dark council, myself, Satan, and Lucifer.

Underneath them are Leviathan and Mammon.

Then below them are Asmodeus and Beelzebub.

It seems that beings like Asmodeus or Beelzebub, deeply related to sexual desire or appetite, are bound to be weak in the Demon World.

But what about after they ascend to the surface?

When they reach the Intermediate Realm?

“It depends on how much magic power is left.”

If one had infinite time and could take all resources for themselves indiscriminately, I would think Beelzebub is the strongest among the Demon King’s army.

No other being can form and control a mass as enormous as Beelzebub.

He is essentially an insect, and nothing reproduces as prolifically as an insect.

Individually weak, certainly only about the seventh strongest in the Demon World, but if only he has abundant resources to create a massive legion, he can stand as the strongest in terms of group or army.

That is Beelzebub.

I even borrowed a bit from Beelzebub’s method when increasing the military strength of the Demon King’s army; his way of augmenting soldiers was truly efficient and effective.

“Seeing dead livestock reminds me of bad things.”

While I left Lucius and Rosmas to book accommodations, I sneaked out to inspect the traces of a dead goat.

“I discovered it not long ago. It was infested with bugs from the inside, so I burned it, dug a pit, and burned it for three days.”

“Well done. The ones inside must have burned to death as well.”

Now it was completely charred and burned, but parasites that must have made the goat their host probably roamed inside, devouring the internal tissues and growing.

I hadn’t confirmed yet, but it probably wasn’t a fly.

It looked more like something that resembled a fly.

“Have you finished your checks?”

“Yes, thank you, elder.”

“Then what did you find…?”

“This could potentially be a matter where we need to call the Holy Knight Order?”

The old man’s expression instantly hardened.

“I still need to confirm, but it could be traces of Asydia?”

“W-what…? Why would those madmen…?!”

“I don’t know either. It doesn’t seem like a simple issue.”

Although Belphegor and Beelzebub don’t have any direct relation, effectively scaring with Asydia since they’re both Demon Kings had certainly its effect.

“So, what should we do?! Huh?!”

“Is there any livestock that recently went missing?”

“W-well, there is, but…”

“Let’s check that and then contact Odrone, right? It’s better to confirm than to make unnecessary commotion.”

“U-um, Witch. Is it really Asydia?”

“We should check because we don’t know.”

“Master!”

Lucius and Rosmas approached me.

They had likely completed the accommodation arrangements.

“Then elder, I will go to the sorcerer who can contact Odrone. If any missing livestock turns up later, please inform me immediately.”

“Ah, I understand.”

I covered the goat’s corpse with straw once more, asked for the elder’s understanding, and moved on to the next location.

“It looks like just a regular house…?”

“It’s a wizard’s workshop, so there’s nothing particularly unusual about the outside. Excuse me. I’m an adventurer introduced by the elder.”

Knock knock.

I grabbed the doorknob with a knock.

As soon as I touched it, a light electric shock sparked, but I quickly infused mana to twist the barrier and opened the door.

Bam!

“Eek!!”

As soon as I opened the door, the sorceress inside screamed and dove under her desk.

Dressed in a witch’s hat and a robe that concealed her entire body, her long brown hair fell messily down to her waist, and her teary eyes had two tear points from her shock.

“Hello. I’m Witch Bel. You are the resident magician of Rastima, right?”

“Y-yes… but why the barrier…?”

“You placed up the barrier first, didn’t you? We were trying to come over here.”

“…Are you a Great Sorcerer?”

The sorceress kept glancing at me anxiously.

In this sudden situation, Lucius and Rosmas behind me looked bewildered, and I pointed at the magician who was slowly crawling out from under the desk.

“She keeps watching us with clairvoyance.”

“…Master.”

“Don’t worry. There’s no hostility. It’s probably just concern for the village.”

Nodding rapidly, the sorceress quickly complied.

“S-so, Witch…?”

“You have a communication crystal to contact Odrone, right?”

“Y-yes. I do manage it, but…”

“But?”

“…I was explicitly warned not to contact unless something special happened…”

“Whether something special will happen or not can be confirmed later.”

I generated formulas in mid-air towards the sorceress.

“For now, let’s do a light skills test, shall we?”

To see if she would be of any assistance.

If she proves to be—

“Uh, um, a formula for transformation magic…? Ah, no…? It seems a bit outdated…?”

“Oh.”

If it works—

“Wait, shall we have a ‘story’ together?”

It seems like I’ve finally found someone to discuss magic with.

*

After exchanging ideas with the sorceress about modern magic, I returned to the accommodation and organized what we discussed about magic onto parchment.

“Master, here’s some tea….”

“Thank you.”

After placing the tea Lucius brought on the desk, I grabbed the quill pen again and focused on magic.

After a heated debate regarding the explosiveness and cohesiveness of flame magic and the method of releasing maximum power all at once, as well as the magic accordingly.

A new magic which allows phantasm magic to affect not only oneself but also the clothing one wears.

In my case, I use floating magic to ride on objects levitating in the air, whereas modern magicians spread wings like angels and fly through the sky with flying magic.

The modern magics I learned from the sorceress had much to offer.

Knowing the enemy and knowing oneself, one need not fear the result of a hundred battles.

To know in detail about the magics changed since 500 years ago and prepare is crucial to prevent facing great misfortunes later on.

So….

“Hey, Master.”

“What?”

“About today’s physical training….”

“……Ah, has it already gotten that late?”

Wrapping up the organizing, I casually finished what I was doing, put the quill back in the inkpot, and stacked up the parchments neatly.

“We’ll start by lightly stretching our necks. You both have changed your clothes, so let’s get right to it.”

Rosmas joined us for physical training.

I gave a gentle stretch to my neck that had been sitting for a long time, and they both mirrored me, entering warm-up exercises.

“Master. Is magic that fun?”

“Magic?”

“Yes. I haven’t seen you so focused before.”

“Magic is indeed fun.”

Using the power of mana to defy the laws of nature and exert influence over the world.

Not in the same way, but through truly diverse methods.

There’s nothing as entertaining as magic.

“If you have magic, you can do anything. For example, there’s brainwashing magic as well, right? If conditions are right, you can turn someone into a puppet that only listens to commands, or there’s magic that takes away control of the body while the persona remains intact.”

“…Is there such magic?”

“Yeah. It’s mainly used by necromancers, but with your strong mental barrier, you and Rosmas should be safe.”

Lucius will have his mind protected by the Holy Sword, and Rosmas, being an elf, inherently has a strong mental constitution.

The reason I mentioned brainwashing magic is to instill a sense of caution regarding it in them.

‘It’s dangerous.’

Though Beelzebub doesn’t use brainwashing magic, there’s no harm in being careful.

“Magic is truly profound. Just changing the formula a bit alters its influence.”

“What about you, Master?”

“Well… this is a fight.”

I pointed to the magic core embedded in my heart.

“The side with the stronger will loses. But as long as you don’t lose your resolve and your spirit remains unbroken, you can maintain your identity. Even a small amount of mana can easily resolve issues like brainwashing.”

“That’s impressive, Witch.”

“Right? But, ironically, it might be challenging to resist physical strength. Without mana to augment my physical abilities, I’m just a weak girl.”

So I must train my body like this.

Even if it’s not a muscular physique, it’s essential to use physical strength when mana isn’t available.

“Master.”

“What?”

“Is there any chance… that I could learn magic?”

“…….”

Something.

I feel like I just got hit on the back of the head.

Kneeling in a mounted stance, I froze for a moment.

“What?”

“Can I learn magic?”

“You want to learn magic?”

“Yes. At least starting with the basics…”

I immediately grabbed Lucius’s wrist and sat him down in a chair.

Then I perched on the armrest of the chair to make it easier to teach.

“M-Master?!”

“You should have said you wanted to learn magic sooner. Hehe, asking the world’s greatest magician for lessons. You can’t pay billions anywhere else to learn what I’m going to teach you.”

I took Lucius’s hand directly and moved it to teach him how to hold the quill pen.

“We’ll start from the basic runes. Magic uses mana, but you can use the power of the Holy Sword instead, so we’ll start with letters first. Got it?”

“Y-yes, understood. But….”

“I want to learn too!”

“Really? Then come over here.”

I pointed to Lucius’s opposite side, and Rosmas shifted her backside onto the handrail, taking her place.

“The natural magic that elves use is a bit different. We’re starting from the basics because we need to teach Lucius, so just take it in proportionately. Understood?”

“Yes!!”

Can someone be this bright?

At Rosmas’s cheerful tone, I placed my hand next to the quill pen Lucius was holding.

“Lucius.”

“Y-yes!!”

“This is the magic you asked to learn.”

Turning my head to the side, I sternly warned Lucius.

“I’ll stuff the concept of magic from beginning to end into you. Hehehe.”

Aura.

Into the profound world of magic.