Recovering from Mana exhaustion was a very bad feeling.
You know the feeling of practicing some high-intensity sport until your body can't stand up? With your lungs demanding oxygen and you feeling like you can't give them enough?
The feeling of running out of Mana is very similar to that, although I didn't feel physically exhausted, I felt my body demanding more Mana while I couldn't provide the Mana it required.
That's because I didn't control myself and wanted to try to do some more spells, even though I had very little Mana in my reservoir.
So I had to lie exhausted for an hour while my body slowly recovered Mana.
Fortunately, after reaching a certain level of Mana, my body started acting normally again, giving me the freedom to move around like a normal person.
Looking at the empty house, I let out a soft sigh.
Coming from another world where I was just an abandoned orphan in the orphanage, only to be thrown into the body of an abandoned orphan in an empty mansion was a big upgrade.
By that world's standards, as long as a child was 4 years old or older, they could live on their own, and since the last members of the Kazuki clan died last year, just after I turned 4, I had to fend for myself in this village.
My luck was that despite the mediocrity of the Kazuki ninja force, during the period when the Makami patriarch was controlling the family, the intellect of the Astaroth lineage meant that he was able to make some good investments, which gave me a generous passive income to support myself.
A total of four stores rented out to civilians and retired ninjas, which brought in around 200,000 ryo a month after taxes.
Considering that the purchasing power of 100 ryo was the equivalent of 1 USD in my previous world, this income of 200,000 ryo was the equivalent of U$2,000, a modest amount for a large clan, but considering that the largest source of income came from missions, it was still a good extra income, but for a child on her own, this money was more than enough.
So even if I didn't want to pursue a career as a ninja, I could still live a quiet life without any financial worries.
But this quiet life couldn't support my Devil potential, as an 'evil creature', combat helped my growth a lot, and as the ninja life would put me on various battlefields, I feel this would be the best way to develop quickly.
Sure, this would also bring risks, but if I practiced the art of "Being and not appearing", where I would hide my true power and show only what I wanted others to know about me, when my true power was finally revealed, I would no longer need to worry about my safety.
Tired of staying at home, I decided to take a walk around the village.
The first place I went was where my body was most familiar, a busy park in the center of the village where most of the children played.
Considering that the population of Konoha was over 100,000 people without much entertainment, the park was always very busy, so little Kazuki Enzai loved to come and play.
It was the only way he could cope with the loneliness of living alone in a mansion.
Fortunately, none of his playmates were in the park, so I just kept walking.
I let my body guide my destiny while I thought about my plans for this world.
From what I remember of DxD demons, their strength grows naturally with age, so most are too lazy to train and just wait for time to advance them to higher levels... but that doesn't mean that training doesn't make them stronger.
Sairaorg Bael was a clear example of this, who despite not having the Power of Destruction like Rias, he trained hard enough to be comparable to an Ultimate-Class Devil at the age of 17 while Rias remained at the power level of a High-Class Devil until the end of the anime.
Several members of Rias' Peerage grew from Low/Mid-Class Devils to High-Class Devil in periods of a few years, showing the great potential that this race had, but which was mostly wasted because of the Devils' laziness to practice.
With such a huge growth rate, showing practically infinite potential, imagine how strong Sairaorg wouldn't be after centuries, or even millennia of training?
Sure, I know the improvement curve would drop, but it was obvious how much potential a demon motivated to train had.
'That may be why the Makami patriarch stopped training and focused only on politics... reaching the peak power level of a village like Konoha was already a great achievement, if he realized that doing nothing would still make him stronger, that may have made him take strength for granted, not imagining that some accident would happen along the way...' I thought disappointedly.
As I know that there are beings much more powerful than the current 5 Kages, I'm not going to become complacent with just the level of strength of an ordinary Kage... but to start down this path I have to train.
'As my Chakra and Mana have merged in my body, I won't need to train the two separately, so my exercise will be divided between three main fronts: Mana Control, Physical Development and Expansion of magical abilities.
Energy Control would be my number one priority.
What's the point of having huge reserves of mana and chakra if I can't use them properly? Even the simple fireball I created with Creativity Magic required concentration and energy consumption. And when I tried to create a perfect kunai, I almost fainted.
So the first step will be to learn to control the flow of my energy. This means daily concentration and control training, perhaps something similar to what ninjas do with the leaf on the forehead exercise or the water and tree walking training.
'If my Mana and Chakra have merged, I can probably do these trainings with Mana too, right?' I asked myself curiously.
Second comes physical development.
Even with my body already strengthened by demon blood, I know that physique counts for a lot in this world. There's no point in having magic if a punch knocks me unconscious.
I don't want to be like the mages in RPGs who only do a lot of damage and have no stamina at all.
So I'm going to draw on the Physical Exercise studies I knew from my previous world in training methods for calisthenics, running, push-ups, endurance... and incorporate magic into that, strengthening the body with mana during training to push me beyond my limits.
And lastly, and perhaps most importantly, expanding my magical abilities.
Creativity Magic] needs to be tested every day. I don't think it's a skill that will evolve through repetition alone.
This magic depends on my imagination, knowledge and mental clarity. This means that studying, something that few in Naruto seem to take seriously, will be my greatest weapon.
The [Kankara Formula] will also benefit greatly from this.
Manipulating phenomena requires me to know what I'm doing.
In time, I believe I will be able to intercept techniques, break them down in real time, reverse their effects or even copy them like the Sharingan.
As I continued to plan how I would train to become stronger, I realized that I was standing in front of the Ninja Academy.
What surprised me wasn't the place, since although the architecture here was very different from the buildings in my previous world, I was getting used to it after walking around the village.
What was surprising was seeing two people walking to school.
A tall, white-haired man wearing Jonin clothes was accompanying a boy about my size, who also had white hair and wore a half mask over his face.
Hatake Sakumo and Kakashi!
'What were they doing at the Ninja Academy?' I asked myself confusedly, trying to remember why.
Then I remembered something I'd heard from other children: the Ninja Academy was open for enrollment, any five-year-old could sign up!
Walking to the registration point, I didn't try to hide and just walked naturally.
The sound of my footsteps probably caught Sakumo's attention, so he looked at me for a second before widening his eyes slightly in surprise. Then a smile appeared on his face.
"Well, well... if it isn't little Enzai." He approached, a friendly tone in his voice. "Long time no see. How have you been?"
The memory was clear in his eyes, and it made sense. It wasn't me, but the old Enzai, Makami Kazuki's grandson.
Makami was one of Konoha's legendary veterans during the First Ninja World War. I remember reading something about him saving Sakumo's life when he was still a newly promoted chuunin, facing his first real combat on the battlefield.
"Good morning, Hatake-sama." I said with a slight smile and a polite bow.
"Sama? You don't need that. You're Makami's grandson. It's good to see you're still around. Are you going to sign up?" He asked with a friendly smile as he looked around.
When he realized that there was no one accompanying him, the smile grew weaker on his face, but he still tried to act normally.
"Yes." I ignored his expression and replied, nodding. "I thought it was time to start my journey as a ninja."
Sakumo smiled with satisfaction and put his hand on his son's shoulder.
"What a coincidence. I was just bringing Kakashi to sign up too." He looked at the boy. "How about you go together?"
Kakashi looked at me sideways, his half-closed eyes not hiding his indifference, or perhaps it was a little antipathy.
It makes sense, the old Enzai was an ordinary child, a bit noisy, perhaps even immature.
Kakashi was always more serious, more mature, someone who hated wasting time and would rather train than waste time playing ninja. He must have considered the old Enzai a nuisance... and perhaps he still carried that impression.
But I didn't care.
After all, I understood where he was coming from.
"If you don't mind my company, Kakashi." I said gently, with a sincere smile.
He sighed slightly and replied dryly. "Do whatever you want."
Sakumo just laughed, as if that were typical of his son. "Let's go, then. I'll let the instructors know you've arrived."
We entered the academy building, and after a few minutes we were sent to a room where some children were going through a quick potential assessment, something that didn't exist in the anime, but which made total sense in a military environment like Konoha.
When they saw Kakashi, one of the instructors immediately approached. "Hatake Kakashi? There's no need for that. The Council has already determined your direct enrollment. Your father..."
"He'll take the test like anyone else." Sakumo interrupted, his tone firm but calm. "My son will get what he deserves."
Kakashi just nodded silently, as if it were obvious.
The instructor hesitated for a moment, but eventually agreed.
Turning to me, he asked. "What about you? What's your full name?"
"Kazuki Enzai." I answered clearly, looking into his eyes.
"Kazuki...? Ah. Of course." The man blinked for a moment and looked at the paper with the names, reading something there, he nodded and began to lead us to the test site.