An old lady was looking at the baby in her arms. The baby was not moving and there was no sign that it would ever move again. Just after losing its mother, the baby too was gone from this world.

Just as the old lady was about to leave it near its mother. She felt her thumb finger being grasped by something small. Turning to look at the baby, she was shocked to see it staring right at her with a curious look. This was a miracle. The life that everyone thought lost was looking at her blinking its big round eyes. To confirm her thoughts, she quickly slapped it on its butt.

"Gyaaaa ...aaa" The distinct wailing of a baby filled the room eliminating the gloom.

But different thoughts were churning through the mind of the newborn soul inside the baby. Having all the memories of past life and living a new life was unthinkable for normal human beings, but there he was looking at the world, alive and kicking. It felt so much better for him.

He looked around to find his parents, but all that he could see were blurs.

'This might be some kind of hospital'. Thought Arun.

He was cleaned quickly before being laid comfortably on a white piece of cloth. Next to him was a baby, crying its throats out.

But then there was nothing. No parent came looking for him. Nor was there any family members excited to see him. He knew he was an orphan that day and he can't expect anyone to come looking for him, same as before. The only family he has is the white-haired future pervert sleeping in a nearby crib.

Taking a deep breath of Konoha air, feeling its purity and energy rejuvenating his soul. Arun was ready for a life in the ninja world. A world of tragedy, war and death. A world in which child soldiers are the norm and no amount of insanity is too much.

"Iks ga to bee baa" (It's great to be back in baby tongue.)

______________

After one year of daily meditation. Arun was finally able to concentrate for more than ten minutes in a row. He was thrilled.

Although as reincarnator, Arun was more than happy to delve right into chakra manipulation. But he was unable to even extract his chakra by combining physical and spiritual energy.

The problem here was his weak body. With almost zero physical energy and a disproportionately large amount of spiritual energy, courtesy of reincarnation with memory. Arun failed to not fall asleep while practising.

His feeble brain cells struggled to keep him awake against all his bodily needs. That includes pooping and pissing every couple of minutes. It was tiresome work.

And the humiliation of someone wiping his ass and changing his diaper bore through his self-esteem leaving behind a gaping hole in his pride.

But that couldn't stop our young Arun from doing everything he could do with his little body. That includes trying to squirm his way into standing up and looking out the window.

Then one day he felt something click inside his head. Then everything changed. A feeling welled up from his being. Trying to show him a path.

Arun closed his eye trying to grasp that feeling. Although nothing physical could be felt. He could sense something new in his mind. What could that be thought Arun?

Arun slowly opened his eyes and turned around to look at the crib between his wobbly legs. The moment he thought of the dimension of the crib. A three-dimensional model began constructing inside his head. It had an accurate measurement of the crib in real life. He could mentally view it from any angle and observe it.

It felt like he had a Computational unit in his brain. Then he began flexing it to limits trying to find its capabilities and limits. Arun tried many things like how any kid with a new toy would do.

He tried adding many more parameters to the crib. He changed the colour, designs and materials. All which he could do in seconds. But when he tried to imagine more objects inside the space. He got a mild headache.

"Of course, there are limitations," Thought Arun before continuing.

He realised after some more experimentation that his brain or a part of his brain was working almost like a GPU but it was not one. He also quickly came to the understanding of its drawbacks.

One of which is that. He had limited memory. He couldn't imagine something so vast like a planet in his brain. He also found out that, with the increase in the number of vertices on an object. The slower he visualises and the higher the strain it has on his mind.

Likewise, he also found out the insane amount of raw computation he can do now. If you ever thought three-digit multiplication was hard. Now he could easily do any multiplication or addition operation in his brain within a limited amount of time. Any would seem very misleading in this case. For better understanding, we can say that. Arun can do almost all the computation a normal personal computer can do with the same speed.

Finally trying out different things. Arun had expended almost all of his spiritual energy, which gave mild headache and drowsiness. Then the realisation hit him.

What should he call this ability? A kekkei genkai or cheat. Although it was a great ability. Arun knows that in this ninja world. There are people with even better cheats, for example, the sharing gun or as people would call it, A 'Sharingan'. So, he didn't feel his ability was very overpowered.

After all, Arun did not become any smarter with this ability. He is still limited by his IQ, So having a computer in his brain would not solve that problem. And this ability will not help him stop a tailed beast bomb or a falling meteor in its track.

Even after cursing the octopus, he still gave me a cheat. Arun felt bad remembering the slimy face of the octopus.

Even after all that, he couldn't keep his sleep at bay.

Dozing off, he slept for an hour before waking up again feeling his wet diaper.

'Fuck the universe. Why don't I even have basic control of my body? I have a computer in my brain for god's sake. I slept for an hour. And now, pissing again. I will control my body to perfection in the next 24 hours.' Thought Arun with his scrunched up babyface.

Arun knew what to do next. Although it was a little shameful. He screamed aloud to call out to the orphanage caretakers or as he would call them big sisters. There was a slight blush on his unblemished cheeks but he continued to increase the volume and frequency of his scream to get their attention.

One of the new big sisters came to him before asking the girl next to her.

'This is the grownup baby right. The one that makes grownup faces when he poops. Look at him blushing, he is so cute!'

'Yes, He is called Itsuki. Now quickly change his diaper or else he will burst your eardrums with his scream.'

Although the soul in the baby was a mature man. He didn't know Japanese. Or else he would have given a tongue lashing to these seventeen-year-old kids. How dare they talk embarrassing things about him.

"Humph.." making a slightly disgruntled noise. Arun or Itsuki as he is called, crossed his arms looking at the new diaper coming his way and chanted 'I can do it.' With firm determination.