Senjutsu and Ki

Life energy or Ki, is the energy that flows on living beings as well as nature. An energy that permeats the whole world but few could even feel or utilize it.

The only way to feel and utilize this energy is through the use of Senjutsu. It is a power similar yet different from devil's magic or magic in general and angel's light power.

While senjutsu can't be said to be the most destructive power, it is very versatile when used properly. An example of it's uses is, it let's the user read the ki of other beings thus letting them track targets from far away distances.

Another use of it is, it can be used to see through illusions by detecting the flow of the spirit or ki of others. These are just some of the many ways on how senjutsu could be used.

.....

Meanwhile on Issei's room, he can be seen sitting on his bed in zazen or lotus position. He has his eyes closed as his hair flutters for some reason.

A few minutes passed by as Issei meditated, suddenly, a faint white aura appeared coating his body. But, he continued his meditation.

A few more minutes passed, the white aura became stronger as time goes before it became fully visible. It was like a white flame wrapping Issei.

Finally, Issei opened his eyes and glanced at the white aura.

"Looks like I succeeded," He smiled

[So you want to practiced senjutsu?]

"Yes, senjutsu is one of the easier ways to become stronger fast. Luckily, Kuroka taught me senjutsu back then."

[You've mastered senjutsu in the future right? But what do you intend on doing with it. Sure, it could strengthen both your internal and external bodies but that's just while actively using it. And even with that temporary boost, changing your heart to a dragon's is still not doable.]

Issei just smiled, "For this current time, that's just how senjutsu works. But during the catastrophe, we discovered another use for it. It is one of the many methods we discovered to let the majority of the population become stronger fast. Unfortunately, it was only discovered when the war was reaching it's end and the population was just 10,000,000 with the majority being former normal humans."

Just remembering those days, Issei lamented. If they just discovered that method earlier, maybe it could have raised their chances of winning.

'No, even with that, we didn't have enough time to prepare.'

[Hmm, a new use for senjutsu, interesting.]

"Do you want to know how it's used," Issei asked

[Of course, I'm interested.]

"Haha, well let me explain..."

Issei started explaining how to utilize Senjutsu to become stronger fast. Basically, the premise of the method was, using nature's ki to stimulate and increase his life energy.

The reason for that is, life energy not only boosts his life span, it also boost his vitatlity and physical strength. That's because, life energy flows through the whole body and gives it energy, so if it increases in quantity, it's possible to also strengthen the body although it's just a bit.

But if he started intense physical training, even with his developing body, it's not dangerous as with the increase in vitality, his healing factor also increases. In other words, while his body is damaged, it's getting healed at a fast rate that it's effects on his developing body is basically voided. So he doesn't need to worry about affecting his growth.

At the same time, his physical strength will rapidly grow as his muscles breaks and tears, after healing it, they become much stronger. Then repeat and rinse and his physical strength will soar.

After the explanation, Ddraig finally understood the process.

[I see, it is a very good method to use in increasing physical streangth. But I wonder why this method wasn't discovered and used in the past.]

Ddraig thought this method is ingenious. He also met many senjutsu user in the past but he hasn't met one who used such methods.

"Haha, it's a crude but fast way in getting stronger, at least physically. Actually, that's just the first phase of the process. Back in the war, this method was used with the help of senjutsu users, assisting our troops," Issei chuckled, " Actually, this method was inspired by how dragons were first born."

[Hmm? How dragons were first born?]

"Yes, dragons are beings made from huge mass of energy, right?"

[Indeed, we are being made of pure energy.]

"One of our researchers back then made a theory, what if overloading the body with energy lets us become stronger physically like dragons. We were desperate back then that we didn't care about risks, so we tested it and the one who volunteered, exploded due to the huge amount of energy, pumped into him." Issei stopped for a moment begore continuing, "After that, we discovered the reason he exploded was because his body was not strong enough, though that should've been common sense. So after some more brainstorming, we created this method of using senjutsu to gather the abundant nature's ki and strengthen our physical strength."

[I see, so the first part of this method is strengthening the body.]

"Yes, as for the second part, let's leave it for later."