Sixteen years old, the Fourth Mizukage

While Naruto Uzumaki had received a solid verbal beating from Rei Kaguya and fallen into memories of the past and self-doubt, on the other side, after Sasuke Uchiha finished communicating with Konoha's higher-ups, he could not help sighing one time after another.

"Sasuke, ever since we walked out of the meeting hall, you have been sighing from time to time… Is it because Lord Fourth's questions were a little too sharp and frequent?"

Seeing his younger brother fall into thought again while facing a plate of steaming hot dango that had just been served, Itachi Uchiha could not help reaching out worriedly to touch his forehead, asking with concern.

"No, it is not that."

Sasuke Uchiha returned to his senses and gently shook his head. With a bit of loneliness and a bit of envy, he said,

"I only felt emotional because I met the Fourth Hokage himself while he was still alive, and from his words and actions, I saw the difference between him and the Third Hokage, as well as Konoha's other higher-ups…"

Recalling that blond man who had earnestly listened to every part of his speech, who always waited until he was prepared before asking carefully considered questions at the right moment, and who could very sincerely apologize for inappropriate parts of his own words, Sasuke Uchiha could not help letting out a long sigh.

If the Fourth Hokage, Minato Namikaze, had not died during the Nine-Tails' chaos and had instead lived properly, governing Konoha as Hokage, then whether it was the voices within the Uchiha clan that wanted to rebel against Konoha or the later night of clan extermination, they should have dissolved silently under his seriousness, sincerity, excellence, and sunshine.

And as Konoha's first Hokage from a civilian background, Minato Namikaze's breadth of mind should also have been able to allow his successor to come from the Uchiha clan, right?

Using the assumption that Minato Namikaze had not died during the Nine-Tails' chaos as a starting point, Sasuke Uchiha's thoughts began spreading endlessly.

He saw Itachi Uchiha being entrusted with heavy responsibilities by Minato Namikaze, ultimately standing out from a crowd of competitors and becoming the Fifth Hokage.

He saw the Uchiha clan further carrying forward its pride and excellence under Itachi Uchiha's rule. He saw himself naturally chasing after his brother's back, secretly competing with him while sincerely protecting his brother's glory as Hokage.

He saw Naruto Uzumaki no longer being rejected, feared, and alienated by Konoha's people because of his identity as an orphan and Jinchuriki. He saw that guy boast shamelessly that he would become an even greater Hokage than Itachi, and then become his rival who spurred each other's progress.

…

Although Sasuke Uchiha knew that if they had not experienced those pains and hardships in childhood, if they had not experienced those heart-rending losses and grief, neither he nor Naruto Uzumaki would likely have grown into ninja as powerful as they later became, and the entire shinobi world might also have been dragged into the eternal dream of the Infinite Tsukuyomi because he and Naruto, the two "saviors," had not grown up…

Sasuke Uchiha still could not stop himself from feeling that compared to becoming a savior who saved the world after experiencing pain and torment, he would rather grow up accompanied by his family, constantly become stronger through healthy competition with Naruto, chasing and being chased by each other, move forward with feelings of half admiration and half unwillingness to lose toward his brother's back, and finally, together with the Konoha shinobi worthy of his efforts and protection, welcome the final battle against the revived Rabbit Goddess.

Perhaps because that fantasy was too warm, Sasuke Uchiha's face, already accustomed to coldness, slowly revealed a soft smile. But looking at Sasuke Uchiha's unconscious smile, Itachi Uchiha's mood grew somewhat heavy.

Using the younger brother he was familiar with as reference, and using the usually indifferent and tense expression of this "younger brother" from several decades in the future as contrast, Itachi Uchiha did not even need to use his brain to think. He knew that this younger brother from the future had not actively chosen to become his current cold self, someone who rarely even showed a smile.

Then who were the ones that had forced him step by step into his current state?

They were the elderly people of Konoha whose thinking was outdated, who clung stubbornly to the old ways and held power without letting go. They were the shinobi who remained bound within the limitations of the profession of ninja, circling in place without realizing it. They were also himself, who clearly did not possess the ability to change everything, yet always wanted to solve all matters alone—arrogant beyond compare.

"There are many geniuses in the shinobi world good at killing and fighting. But have they really killed their way to any result? No. The only results they obtained were that war never changes, and an extremely elementary theory of chained hatred. Nothing else."

"As long as two leaders who harbor hatred reconcile with each other, then two villages with conflicts of interest can become friends from that point on and never invade each other again? As long as everyone is willing to sit down and talk, true peace will arrive? As long as the shinobi all long for peace in their hearts, no one will ever want to start a war again?"

"No one has seriously considered these questions, peeled out the core contradictions and conflicts within them for study, and then taught the analysis of these problems to more people who can understand them. If that remains the case, shinobi will forever be nothing more than knives in the hands of others."

"So read more books, study more history, and properly establish philosophy and humanities with shinobi-world characteristics from nothing. That is far more valuable than you trying every possible way to open a pair of Mangekyo Sharingan… Hm, at least while I am here, that is the case."

Suppressing Rei Kaguya's reminder that had suddenly surfaced in his mind, Itachi Uchiha blinked. Then, looking at Sasuke Uchiha, who could not help showing difficulty because of the skewer of extra-sweet four-color dango in his hand, he called his name very seriously.

"Sasuke."

"Mm? What is it, Itachi?"

Sasuke Uchiha swallowed the dango, which was somewhat too sweet for him, with difficulty and looked doubtfully at Itachi Uchiha, whose face was solemn.

"You came to this era through that Otsutsuki treasure capable of traveling through time and space, correct?"

"Mm, that is right. Is there a problem?"

"If it can bring people from the future back to the past… then can it do the opposite and bring people from the past to the future world?"

Itachi Uchiha's question made Sasuke Uchiha subconsciously show a vigilant expression. But when he thought that the person before him was Itachi Uchiha, the good older brother who had not experienced any of that darkness, his expression immediately relaxed again. With a somewhat uncertain tone, he speculated,

"It should… be possible, right? After all, Urashiki Otsutsuki previously wanted to use the 'Plow' to travel through time back to the shinobi world's past, seize the Nine-Tails from Naruto before he had grown up, then bring it back to our era as material to revive the Ten-Tails… Why are you asking this, Itachi?"

"Probably because of curiosity, and because of a rather mad idea that suddenly appeared."

Itachi Uchiha organized his thoughts, then looked at Sasuke Uchiha, sat upright, and said with sincere attitude,

"Although I know this idea is somewhat crazy, and also somewhat rude and offensive… if possible, when you and the others return to the future, I would like to follow you to the future you live in and take a look."

"Why did you suddenly come up with that idea, Itachi?"

Sasuke Uchiha did not directly reject Itachi Uchiha's request. Instead, he very seriously asked the brother in front of him, who looked so scholarly, for the reason he wanted to do so.

"Perhaps it is because, before I officially become a teacher who educates others, I want to increase my own knowledge and experience a little more. And through studying the historical development of a world where there is no Lord Mizukage who was born knowing everything, I want to more deeply analyze the origin, development, and limitations of the profession of shinobi, so that the people of the shinobi world can more easily and clearly understand what the reforms that began from Kirigakure were truly for."

Itachi Uchiha gave an answer that, to Sasuke Uchiha, was unexpected yet also reasonable.

"You still have that personality of yours, always considering things for the majority, Itachi."

Sasuke Uchiha put down the dango in his hand and said with a somewhat nostalgic tone.

"It is not entirely for the sake of the other people of the shinobi world…"

Itachi Uchiha pushed up his plain glasses and said frankly,

"I have received much teaching from Lord Mizukage, and also learned a great deal of theoretical knowledge. Among those teachings is one saying that practice is the sole criterion for testing truth. Going to your era to walk around and take a look, and seeing whether the history under normal circumstances can be analyzed and verified using the knowledge I have learned…"

"In other words, this counts as your personal desire, Itachi?"

"Ah, just consider it my selfishness, Sasuke… Is that all right?"

Itachi Uchiha asked with slight nervousness.

"I will go talk to Naruto."

Sasuke Uchiha took a deep breath and held Itachi Uchiha's hand with his right hand.

"After all, this is the first time I have had the chance to help you realize one of your own selfish wishes, Itachi."

"Sasuke…"

"Itachi…"

The two looked at each other just like that, each seeing the happy self and the moved other party in each other's eyes.

And on the street not far from where they sat, Sasuke Uchiha (younger), who, unwilling to accept his failure at eavesdropping, had followed the two all the way here together with Naruto Namikaze, was currently so angry that his face turned red, then green. He looked as though opening the Sharingan, or even the Mangekyo Sharingan, on the spot would not be strange at all.

Naruto Namikaze, standing beside him, gleefully fanned the flames with a face full of schadenfreude.

"Hey, don't you think that uncle version of you is more suited to staying by your dear big brother's side than the real you?"

"Huff… huff… Na! Mi! Ka! Ze! Naruto! Do you want to die that badly!?"

"Angry? But am I wrong? Your dear big brother has already promised uncle-version-you to go see the future with him, and he even admitted that this was his personal selfish wish… Has he ever said something like that so seriously to you, Sasuke Uchiha?"

"…Naruto Namikaze."

Sasuke Uchiha (younger) took a deep breath.

"What?"

Naruto Namikaze tilted his head and asked back with absolutely no self-awareness.

"I'll kill you! A! Thousand! Times! And! It! Still! Won't! Be! Enough!!!"

With a pair of blood-red three-tomoe eyes, Sasuke Uchiha (younger) angrily pounced toward Naruto Namikaze. The two childhood bad friends instantly started wrestling with each other right there.

And Sasuke Uchiha (older), who noticed the commotion because of the nearby passersby's cries of surprise, could not stop the corner of his mouth from twitching because of the pair of three-tomoe Sharingan flashing inside Sasuke Uchiha (younger)'s eyes. He revealed a very embarrassed expression.