Mental Contamination

Little Sasuke had gradually grown into a graceful, handsome young man.

One night before Neji was due to graduate from the Ninja Academy, he and Sasuke entered the secret chamber beneath the Uchiha Compound.

—They had dug the chamber bit by bit using Earth Release.

"Damn it, Sasuke, be gentler. It hurts when you use too much force!"

"Okay. I'll do better next time."

"..."

"You really are talking less and less," Neji could not help complaining.

Without a word, Sasuke put away the medical kit. Neji got dressed as well. While hunting yesterday, he had nearly been arrested by Root on the spot. Though he had escaped successfully, he had suffered serious injuries, and Sasuke had just been applying medicine to them.

The two rose to their feet. Along the right side of the chamber stood an enormous display wall divided into numerous small compartments, filled with wide-mouthed glass jars and petri dishes containing all kinds of organs.

Sasuke was conducting biological experiments, and Neji was one of the participants.

A few years ago, Sasuke had suddenly become as taciturn as he was now. Although he had already been quiet after the Night of the Massacre, others might not have noticed anything unusual. But Neji, who was especially close to Sasuke, had clearly sensed that something was wrong.

At times, Sasuke gave off an extremely sinister, ominous aura. Most of the time, he concealed it well, and it only leaked out unintentionally during battle.

Not long after that, Sasuke had invited Neji to join the experiments. Konoha provided the experimental materials free of charge.

Perhaps the disappearances had become too rampant, prompting the Third Hokage to make the rare decision to investigate thoroughly. Otherwise, Neji would not have been injured by accident. Unfortunately, the Third Hokage had still miscalculated. He had not anticipated that Neji could use an alien power outside the chakra system.

Before conducting human experiments, Sasuke had also performed a large number of animal experiments, including animals he had purchased under the pretense of keeping pets, creatures caught in the Forest of Death, deer from the Nara Family, dogs from the Inuzuka Family...

Yet in this underground chamber, only two colonies of ants remained alive. Everything else had been discarded as garbage.

The two ant colonies had hatched from eggs laid by the same queen, yet after several generations of isolated breeding, they had nearly evolved into two entirely different species!

If Mendel had been here, he would surely have cried out in amazement. The cause of it all was the miraculous chakra.

Sasuke had infused the ant colonies with different kinds of chakra, and chakra from different sources had directly caused the colonies to mutate!

Later, he had infused chakra into reptiles, mammals, and even humans. Though the changes had not occurred as quickly as they did in ants, they were still quite obvious.

The reason for these experiments was that Asura's chakra had displayed an even stronger contaminating nature than it had in the original story.

Natural disasters had been unceasing over the past few years. Perhaps something had stimulated him, or perhaps the Sage of Six Paths had secretly intervened. In any case, Naruto Uzumaki had matured ahead of schedule, especially his "talk-no-jutsu." Ordinary people simply could not withstand it!

In the manga, Sasuke and Neji had both been beaten up by the Hokage, then inexplicably came to agree with him like idiots, their wills completely reshaped into the Hokage's form.

Neji had originally been a youth burdened by deep hatred. The Caged Bird had bound his entire life and killed his father. He had sworn to take revenge on Hyuga Hiashi and the Hyuga Main House.

After the Hokage beat him up in the arena, he immediately changed. "My father, Hizashi Hyuga, sacrificed himself for his elder brother in his role as the younger brother!"

The Caged Bird was still on his forehead?

Whatever!

His father had been tortured by Hyuga Hiashi with the Curse Mark?

That did not matter!

In short, the Hokage was right! Obsessing over whether destiny could be changed was a boring subject. In the end, Neji even died blocking a blade for the Hokage, walking the same path as Hizashi Hyuga.

—When Neji first encountered this manga plot, he had only thought it was toxic.

Perhaps Sasuke was the only person in the entire Shinobi World who could somewhat resist the Hokage's contamination, but even he had ultimately failed to escape it.

The others were even worse. Gaara, for example, had simply let go of his past after the Hokage beat him up, transforming from a homicidal maniac into a warmhearted nice guy.

After Nagato was defeated, this man who had personally killed his teacher suddenly began believing in the Hokage's theory of "mutual understanding," then gave his life to use the Samsara of Heavenly Life Technique to revive Konoha's dead.

It was utterly absurd. Nagato ruled the Land of Rain, yet he had used his own life to save foreigners. While doing so, he seemed not to have considered at all what would become of his own country.

In Boruto, Sasuke and Sai went to the Land of Rain to investigate Kara, only to find Hidden Rain ruined and unstable. The Hokage's promise to Nagato had been nothing but hot air. A Konoha shinobi named Yeno had even personally told Boruto and Sarada that the peace after the Fourth Great Ninja War applied only to the Five Great Nations; conflicts among the small border countries had actually become more frequent.

Obito Uchiha was much the same. He had been so devoted to Rin Nohara and the Eye of the Moon, yet in the end he had defected with ease and dreamed of becoming Hokage. The more one thought about it, the more terrifying it became!

The Hokage's contamination could twist one's will, making people abandon their original intentions and betray their beliefs. This had already far surpassed the scope of ninjutsu. Sasuke had no choice but to guard against it, which was why he had begun the biological experiments.

Yet during the experiments, Sasuke had discovered in shock that the Hokage's contamination was not unique. More precisely, this "contamination" was a property of chakra itself; the Hokage's chakra was simply rather special.

Rapidly breeding insects illustrated the issue well. Sasuke and Neji had each injected chakra into two batches of eggs from the same queen ant. After several generations of breeding, the ants that received Sasuke's chakra grew beautiful patterns on their bodies and became poisonous; the ants that received Neji's chakra became much stronger, and their eyesight evolved dramatically.

This showed that chakra contained a certain kind of "information," information sufficient to alter biological traits. Orochimaru's Curse Mark was a fine example: those who received it would have their bodies become suitable for Orochimaru's reincarnation.

After repeated experiments, Sasuke had confirmed that this "information" was personal will. The purer and firmer a ninja's ninja way, the stronger the personal will within their chakra. The chakra will of the strong could assimilate the chakra will of the weak.

To prevent themselves from being contaminated by the Hokage's—Asura's—will, Sasuke and Neji had tried many methods using their meager biological knowledge. Unfortunately, they had gained nothing so far.

But they had accidentally discovered an effective way to dig a pit for Konoha: the two secretly infused their own chakra into the children at the Ninja Academy...

Without realizing it, Sasuke and Neji's moral bottom lines had already become very low. But shinobi were a group steeped in blood and killing. Whose hands had not been stained with a few lives? In any case, Sasuke did not think those shinobi who killed for missions were any nobler than he was.

—Self-deception could keep one in a pleasant mood.