It wasn't strange that Neji would ask such a question. If it were anyone else in the shinobi world—anyone other than Uchiha Keizumi—they would probably be just as stunned after hearing Hiashi's words.
After all, in the understanding of most people in the shinobi world, the shinobi world itself was already the entirety of existence.
"Just like you're thinking—the sky beyond this land is what lies outside the shinobi world!"
Since Hiashi had already decided to reveal secrets known only to the main family head, there was naturally no need to keep anything back.
"According to the ancient records of our Hyūga clan, we are not originally a clan of the shinobi world—we come from the moon!"
"And on the moon, there exists another branch of our kin—distant relatives of the Hyūga clan!"
"Or rather, the Hyūga clan should actually be called the Ōtsutsuki clan!"
"You still remember Hinata's third birthday, don't you?"
"That day, those clansmen from the moon came to see her."
Hiashi seemed to think this wasn't shocking enough, and went on to reveal, in full detail, that Ōtsutsuki Toneri had once come to Earth when Hinata was three years old.
"They can come to the shinobi world…"
Neji began to understand Hiashi's concern. If every member of the Hyūga clan were branded with the Caged Bird Seal, then the branch on the moon could completely control the life and death of the Hyūga clan.
"More than just 'can come.' The Caged Bird seal itself was created to guard against them!"
"According to our clan's records, several hundred years ago, that branch on the moon slaughtered members of our Hyūga clan on a massive scale. Left with no choice, our ancestors developed the Caged Bird seal."
"That way, even if those people from the moon tried to massacre us again, the main family could activate the seal and ensure they gained nothing!"
Hiashi let out a cold laugh. Did they really think the moon's Ōtsutsuki could create the giant Tenseigan on their own?
That thing had always involved the Hyūga clan—or rather, most of its composition came from the Hyūga clan itself!
"But if they're our kin, why would they slaughter us?"
Neji was confused. If both sides shared the same ancestor, he couldn't understand what reason there could be for such hostility.
"Because of the Byakugan."
"Or rather… for a higher evolution of the Byakugan."
"The Hyūga clan's Byakugan stands alongside the Uchiha clan's Sharingan—not as empty boasting, but as fact!"
"You know that the Sharingan evolves into the Mangekyō through intense emotional stimulation. So what does the Byakugan require to evolve further?"
Since Hiashi had already revealed the deepest secrets of the clan, he naturally wanted Neji to face his identity head-on.
At the very least, he needed to recognize that the Hyūga clan had never been inferior to the Uchiha.
Not in the past. Not now. And not in the future.
"It requires purity—absolute, unparalleled purity!"
Without waiting for Neji to figure it out, Hiashi gave the answer himself.
"For the Uchiha, the Mangekyō requires extreme emotional shock. But for the Hyūga, further evolution requires the purest bloodline—the purest Byakugan."
"And among your generation, Hinata's Byakugan is the purest—so pure that the Ōtsutsuki on the moon called her the 'Byakugan Princess.'"
"In other words, Hinata has the potential to awaken a higher form of the Byakugan."
"If she truly awakens that kind of eye, then across the entire shinobi world—no, perhaps only the legendary Sage of Six Paths would be able to rival her power!"
"And that is why, despite knowing her personality isn't suited for it, I have delayed placing the Caged Bird seal on her!"
Hiashi spoke slowly. According to the main family inheritance rules, even he, as clan head, could only retain one child as part of the main family. In the past, he had always used Hanabi's young age as an excuse.
But only Hiashi himself knew just how much potential Hinata truly possessed.
It was just that, as her father, he had been too rigid—he didn't even let his own daughter eat her fill. Otherwise, given that even the Ōtsutsuki on the moon had designated her as the Byakugan Princess, she might truly have awakened the Tenseigan.
Even if her eyes only started to take on a faint blue tint—wasn't that already a sign of evolving toward the Tenseigan?
Then again, perhaps Hiashi had deliberately restricted her diet. After all, if Hinata truly began awakening the Tenseigan, what would they do if the Ōtsutsuki from the moon came to take her?
"Under normal circumstances, the only way for the Byakugan to evolve further is through natural awakening."
"But several hundred years ago, the Ōtsutsuki on the moon came up with another method."
"They gathered large numbers of Byakugan—thousands, even tens of thousands—and fused them all together. That way, they could forcibly create a higher form of the Byakugan!"
"And that kind of eye is on par with the eyes of the Sage of Six Paths—it possesses the power to dominate the entire shinobi world!"
Hiashi had essentially laid bare all the Hyūga clan's deepest secrets. As for what Neji would choose…
"An eye… capable of dominating the shinobi world…"
Neji fell into a daze. He had never imagined that the Byakugan could evolve further—nor that such evolution could grant power on that level.
"Did the Ōtsutsuki on the moon succeed several hundred years ago?"
Neji took a deep breath. He now fully understood why the Hyūga clan clung so tightly to the Caged Bird seal.
If the Ōtsutsuki on the moon had once descended to massacre them—and even came again when Hinata was three—then if the seal were ever lifted, those distant relatives could very well launch another slaughter.
"They failed."
"If they had succeeded, there would be no us—and no shinobi world as it is now!"
"The Ōtsutsuki on the moon bear the duty of purging the shinobi world. If it becomes tainted, they will use the Tenseigan to cleanse it."
"You and I both know what the shinobi world is like. The fact that they haven't attacked yet isn't because they're kind—the only explanation is that their Tenseigan plan never truly succeeded."