Sukuna! Pay Your Rent!

Konoha, year 41.

The Second Shinobi World War's end was followed by a baby boom, and this period perfectly coincided with a new batch of recruits entering the Ninja Academy.

At five and a half years old, Kakashi was already there to welcome the new students as their representative.

"Hey! Kakashi..."

Goggles, in his childhood form, approached the young boy with dead fish eyes and a broom-like haircut.

Casually pushing Obito away with a hint of annoyance, Kakashi retorted, "Idiot, get away from me."

Obito, usually carefree, was acting strangely hesitant, as if he had something important to say but couldn't bring himself to.

"Obito, is there something you want to tell Kakashi?" a girl with purple markings on her cheeks asked, stepping closer.

This was Miss Rin Nohara, the only casualty from Minato's team during the future Third Shinobi World War.

"Idiot, if you have something to say, spit it out! Lord Hokage and the others are about to arrive!"

The Ninja Academy didn't have a strict system; semesters were half-yearly, and new students were admitted each term.

The duration of study was also flexible, generally depending on the battlefield situation.

If there was no war, you'd study longer. If there was a war, you'd graduate early.

After all, no matter how beautifully one might describe the Ninja Academy, in the end...

It was just a training facility for assassins.

As if making a firm decision, Obito leaned in and whispered in Kakashi's ear:

"Kakashi... one of my clansmen is enrolling today, he..."

"He's a terrifying guy! He especially targets me!"

"You guys absolutely must not be fooled by his demeanor, he's a truly, truly bad person!"

"And... I heard the clan is letting him into the school this time to deal with you... Ouch!"

Thwack...

A small stone rolled from the back of Obito's head, making a crisp sound.

"Goggles, badmouthing people behind their backs isn't a good habit."

If there were some background music and a scattering of cherry blossoms, it would truly feel like a melodramatic romance drama.

Alas, there was none.

"Bastard! My name isn't Goggles! I'm Uchiha Obito!"

"Okay, Goggles, I understand, Goggles."

The boy speaking had short, curly black hair and bright, expressive eyes. His smile exuded innocence and purity.

Goggles... Obito's face immediately turned red. If Rin hadn't held him back, he would have charged at Kagami Uchiha for a fight to the death.

Kagami Uchiha was the boy's name, the same as one of the Second Hokage's subordinates.

He was originally an orphan of the Uchiha clan, adopted by Kagami Uchiha's wife.

To commemorate her deceased husband, she gave him this name.

Well... I must say, people here certainly have such a habit.

Just like how later, Sasuke Uchiha borrowed the name of Sasuke Sarutobi, the father of Hiruzen Sarutobi.

In their tradition, this represented respect and remembrance.

Of course, Fugaku doing this was probably a gesture of submission.

Yes, Kagami Uchiha knew the future trajectory. After all, the day before he transmigrated, he had spent all night arguing with others on a forum about the "Konoha timeline."

In the end, neither side could convince the other, despite presenting a mountain of evidence.

It was too messy, impossible to untangle, simply impossible!

They had originally agreed to fight again after a day of rest, but Kagami Uchiha broke his promise.

Fine, I want to see what the hell is going on with this timeline!

Looking at the trio of young children before him, Kagami Uchiha felt a pang of emotion.

If he were an outsider, he might have quipped, "Kamui can't hide his tears."

But as an Uchiha...

It wasn't funny at all.

If he didn't know that the fundamental reason for the Uchiha clan's destruction stemmed from problems left over from the village's founding, simply eliminating Obito wouldn't have stopped the situation from escalating.

Kagami Uchiha had wanted to get rid of him for a long time.

"Kagami, don't bully Obito!"

An old woman, holding a baby with the nascent shape of a dango nose despite its young age, spoke up.

This infant is Kagami Uchiha's sworn brother, who would later become the Swift-Moving Shisui.

"Sigh~"

"Grandma, I was just affectionately giving him a nickname. Look how fierce he is, like he's about to rush over and hit me on the head~"

"Ah!!! Rin! Let go of me! I'm going to beat him to death!"

"That pretty young lady, let him go. I'd like to see how he's going to beat me to death."

Watching the two bicker at the school gates, Kakashi shook his head helplessly.

"Kagami Uchiha, right? Be quiet and prepare for the entrance ceremony. Lord Hokage and the others will be here soon."

The maturity of ninja world children was truly extraordinary. Children of five or six in his original world could barely express a complete thought, while here, those who were a bit faster were already killing and setting fires.

Kagami Uchiha sized up Kakashi with interest. "Dead fish eyes and a broom-head, Kakashi?"

Thwack

A large "well" symbol appeared on Kakashi's forehead, and he clenched his fists tightly.

"I-am-Hatake-Kakashi!" Kakashi emphasized each word.

This was practically nickname bullying! This nickname was even worse than that idiot's!

Obito, who had been red-faced with anger, now wore a different kind of red on his face.

"Hahahaha! Dead fish eyes and a broom-head!! Hahaha... muffled"

Rin Nohara covered his mouth, nodded to the others, and dragged the blissfully happy Obito away.

Rage, excitement, happiness... Tsk, if he was provoked a little more, he might even awaken his Sharingan.

Walking step by step towards Kakashi, Kagami Uchiha patted his shoulder with a harmless smile. "Please take care of me in the future, Kakashi-kun."

"Grandma, hurry up and take Shisui home, Kana~"

Once all the children for the semester had arrived, a not-too-old Hiruzen Sarutobi took the stage to give his speech.

It was the same old Will of Fire, unchanged since the First Hokage passed it down. A vague, contradictory set of values.

Growing more bored by the second, Kagami Uchiha narrowed his eyes, his thoughts sinking into his mental space.

Within the mental space, a cube with an overall dark red hue, a vermilion iron gate split it in two.

A thick scent of blood emanated from beyond the sealed bars.

Above countless withered corpses, a god of slaughter soared through a sea of blood.

"Ryomen Sukuna."

His name came from a mythical demon with two faces and four arms. He was once a real human who, during the peak era of sorcerers a thousand years ago, defeated all sorcerers single-handedly.

He was the symbol of evil, a ferociously brutal King of Curses!

Now, two souls from different timelines converged in the ninja world.

"Good morning! Four-arms!"

From beyond the seal, a massive shadow loomed, and a pair of scarlet eyes shot out fierce glints.

"Brat... I told you..."

"Do not look up at me without permission!"

Terrifying darkness swept out but couldn't penetrate the seal in the slightest.

Kagami Uchiha smiled and looked up, completely ignoring Sukuna's threat.

He had been a bit scared at first, but after trying a few times, Sukuna hadn't been able to break through the seal and kill him.

This was familiar territory for Kagami Uchiha. Arguing through a screen, what was there to be afraid of!

Moreover, as he grew older, he found he had gained some control over this seal...

"You should be grateful to be hiding inside my body. I heard they're already sending Goku after you."

"Who's Goku?"

Kagami Uchiha raised his small hand and punched. Thump.

"Someone who can punch the Earth to pieces with a single, light punch like this."

Sukuna was so angry he laughed.

"Brat, there has never been such a powerful being from ancient times to the present. What nonsense are you talking about?"

"Short hair, short-sighted fool," Kagami Uchiha pouted and waved his hand.

"Let alone Goku, the people in this world have already beaten you up one by one."

"Do you know what that means? It means a group of people, each of whom can pick you up and hang you out to dry..."

"Silence!"

Sukuna, in his original form, would never have lost his composure so easily, but things were different now...

This damned seal left him without even the slightest possibility of taking over the brat's body.

He couldn't even sense what was happening outside.

Damn it!

He had just killed Gojo Satoru and hadn't even had time to give his victory speech before being thrown into this hellhole!

What the hell, is Space Slash that potent?!

From a corner of the seal, Kagami Uchiha saw a wisp of black energy seep out before resealing the space.

Skillfully, he picked up the wisp of black energy and swallowed it. Some techniques related to slashes appeared in his mind.

"Alright, that's all the rent for today. I'll be back once I've digested this."

"Bye-bye~"

"Bastard! Come back here!!"

In the darkness, Ryomen Sukuna raged impotently.