Tensei Shitara Slime Datta Ken

These people, despite being human, become able to utilize the power which has the same nature as magic.

That might sound good at first but taking in that kind of energy into one's body is extremely difficult.

Or rather, it's impossible for your general public.

And that's exactly why they train their bodies into a suited vessel, discipline their mental capabilities and strengthen their spiritual body.

It seems like the demon lord Ruminas optimized this and has already created a breeding ground for producing quite strong Holy Knights.

However, even then, apart from a portion of the prodigies, others only can go as high as to borrow a portion of lower rank elemental spirits' strength.

And that too comes with a time limit.

They momentarily exceed human limits and overwhelm the enemy.

That's one of the many techniques which make the Holy Knights the strongest knights.

The strength of a spirit and the techniques of a human.

That's the secret to the strength.

Once you are able to completely use the strength of a higher ranking spirit and the strongest techniques devised by mankind, that's the hero level.

Shizu-san fused using a skill but she had reached this territory.

The reason I won was only because I was lucky.

To be completely frank, it was because my compatibility against her was good.

When I inspected the fight later on, I was told that by the Great Sage.

Say that earlier!-or so I thought then but I wouldn't want to hear something negative like that during a fight. And so it was all good as a result.

Kenya and the others fused with the spirits at the soul level.

Their bodies grew and got used to that power.

—Putting aside exceptions like Shizu-san and Kenya and the others.

I kept on explaining these to them while keeping the concrete stuff hazy.

Now then, it's about time.

Let's change the topic here.

"I think you now properly understand that it is extremely difficult to freely handle a spirit's powers in a human's body. If so, then acquiring this strength in a human's body—in other words, being able to use this mysterious power, what must one do to be able to do this?"

I looked around at everyone listening to me while asking that question.

Being asked a question suddenly, they were perplexed.

However, there were those who were fast in catching up too-

"The way Satoru-sensei phrased that right now—not use the spirit's strength, but use the mysterious power. In other words, if it's a high ranking being other than spirits, it might be easier to use even in a human's body?"

He came presenting a conjecture coming straight for the core.

I smiled and said,

"As expected of the prodigy of Ingracia Synthesis Academy. That's quite some insight you have there, Julius-kun. Or is it that since the royalty of Ingracia kingdom are well acquainted with spirits, it is only natural for you to know? Then, let me ask specifically. What do you think that is?"

Before I realized, Julius' noble-like attitude of looking down on me had disappeared.

His anger probably disappeared too while he was listening to the explanation.

It seems that he has acknowledged me as a teacher—no, maybe as something more.

Julius looked hesitant to answer to my question.

However, the answer was already in his mind.

As if he didn't want to speak of it, he opened his mouth only to close it again. But then he drastically went ahead and said it.

.

"Demon?"

I deepened my smile and applauded.

"That's correct."

Not angels, but demons.

There's also a reason for that.

As angels are pure, it is harder for them to exist in places other than the heaven.

Although the situation has somewhat changed now.

In the first place, demons were more suited for battle.

Well, there are a few more reasons to it other than that…

There are quite a few who can employ a demon.

Most of them do it by a ritual summoning but there are also some who summon demons with magic.

First class wizards, called the Dark Summoners.

The limit for the employment is up to greater demons but a human's body is enough for that.

On top of this, if the vessel is trained…

They can acquire extraordinary strength without training like a Holy Knight.

Moreover…

"If I were to add, there's an effective way to strengthen one's body. Surely there are people here from NNU Magic and Science Investigation Academy who know of it?"

As if the NNU students were nervous, they flinched.

But no one answered.

"Armored Corps—one of the previous Empire's 3 biggest army corps. The soldiers who were enlisted there seemed to have undergone black magic remodeling surgery and became super soldiers but—"

After I said that much, the instructors also realized.

"You don't mean…"

"Black magic remodeling surgery is supposed to be forbidden due to inhumane methods… Besides, the surviving scientists are—don't tell me, those scientists are…?"

"No, even if it's so, it doesn't make sense. Even if black magic remodeling surgery can strengthen the body, it would only go as high as A rank at most."

Heinrich declared.

As expected of a researcher, he knows more than combat types.

"Exactly. Certainly, from the information I gathered, there are very few who have gone up to A rank. And that strength wouldn't come close to a semi-demon lord class. However—what's important here is, strengthening the body."

After I hinted that much, Heinrich also realized.

"I… see, a demon only wants a strengthened body, eh… If a demon dwells in a strengthened body, even if it's a greater demon, they might have the strength to beat a holy knight. And that—"

In other words, that's Demon Fusion.

Well, that's about right.

The strong being of this island, Poison Tiger, who has little combat experience, seemed crude considering it is a semi-demon lord class.

In contrast, if Magnus, who has a ton of combat experience, were to acquire the strength of a demon…

It wouldn't be weird even if he acquired strength exceeding that of Poison Tiger.

Moreover, the chances of black magic remodeling surgery progressing in these past 10 years is quite high.

There's probably no mistake in thinking that Irina, the researcher who seemed to be the mastermind behind this, is the leading person behind that research.

"Well, that's about pretty much it. With this, Magnus' strength should be easy to comprehend to a certain extent."

Saying that, I brought the talk to a finish temporarily.