Defend?
How could they have defended against it?
Setting aside the fact that this event left almost no trace in the recorded history of the shinobi world, just recalling the fragments from that movie-like memory was enough for Boruto to feel certain—
That war had been unimaginably cruel, a conflict that swept across the entire world.
At that time, the Heavenly Clan stood at its absolute peak. Once the Golden Tenseigan was activated, no one in the ninja world could rival them. And yet… the war ended inconclusively.
Not only did the Heavenly Clan retreat to the moon, they even began to suffer mysterious losses afterward—until, by the time of the movie, only a single survivor remained: Ōtsutsuki Toneri.
After a moment of thought, Boruto asked, puzzled,
"The Heavenly Clan's invasion of the ninja world should've happened before Hashirama became the God of Shinobi, right?"
"Otherwise, Konoha would've had records of it. But when Toneri kidnapped Hyūga Hanabi, even Konoha didn't know where the enemy came from. In the end, it was the Hyūga clan head who revealed that they were on the moon."
"That means the Hyūga clan already knew about the moon clan."
The White Snake Sage narrowed her eyes slightly.
"It seems you're quite knowledgeable about the history of the shinobi world."
"I specifically looked into it," Boruto replied calmly.
She didn't press the issue further. Still, Boruto's thinking was far too forward, almost alien for someone born into the ninja world.
Ryūchi Cave possessed terrifying intelligence-gathering abilities. It was said that anything happening in the shinobi world would eventually reach her ears.
Given what she had lived through, it wasn't surprising that she knew of histories lost to everyone else.
"Indeed," the White Snake Sage said slowly, "as descendants of the Amemura lineage, the Heavenly Clan surpassed the ninja world in both talent and power."
"The only way the ninja world could resist them back then… was through the sacrifice of the Hyūga clan, who shared the same bloodline."
"This is the bloodstained sin the Hyūga bear."
Boruto frowned.
"If the Hyūga rose and defeated the Heavenly Clan, then shouldn't they be heroes of the ninja world?"
"But relying on taijutsu alone… It's hard to imagine them overturning a war of that scale."
"The truth," the White Snake Sage continued, "is that the Hyūga saved the ninja world—but they were never known for it."
"They buried that history themselves. That's why their descendants are unaware of the glory their clan once held."
Boruto fell silent.
She was revealing a history long sealed away… but why?
What benefit was there for her in telling him this?
Ryūchi Cave was not a charitable place. Only madmen hungry for power ever came here. And those who granted power to madmen were themselves extreme beings.
They neither despised the weak nor judged good and evil. Their only rule was simple:
Pass the trial, and you earn the chance to become stronger.
Anyone could rise—Yakushi Kabuto was the perfect example. His obsession with knowledge and Orochimaru had driven him to madness, even to the point of joining Obito and igniting a world war.
"This is a gamble," the White Snake Sage said, curling her lips into a confident smile.
"A gamble that your future is bright enough."
"A gamble…" Boruto murmured.
Another stake had just been placed on the table.
He nodded.
"Go on. Why did heroes who saved the ninja world become sinners?"
The White Snake Sage was silent for a moment, as if she'd inhaled smoke the wrong way. After a few steady breaths, she finally spoke.
"A bird in a cage."
"Huh?" Boruto froze. "What does that have to do with the branch family system… and the Caged Bird Seal?"
She chuckled softly.
"Tell me—haven't you noticed that no matter which nation captures a living Hyūga, they can never obtain the Byakugan?"
"Perhaps it's because the Caged Bird allows the main family to control the life and death of the branch family."
She tilted her head slightly.
"In your view, is that merely imprisonment… or something else?"
Boruto didn't answer immediately.
His thoughts drifted back to the Fourth Shinobi World War—
to the man who had thrown himself in front of Hinata without hesitation.
The cage of the bird was undeniably cruel. Death was the only way out… yet even death was not true freedom.
Even Hyūga branch members revived by Edo Tensei still bore the mark of the Caged Bird Seal.
Neji's life flashed through Boruto's mind—
his talent, his resentment, the way he was never entrusted with true authority, always addressed as "Hyūga-sama" instead of by name.
Would the strong willingly submit to the weak?
Commanding strength always came at a price. Even in the real world, bodyguards were expensive for a reason.
So Boruto finally said,
"It's imprisonment… but it's also protection."
The White Snake Sage stared at him in surprise.
"How do you know?"
"You should understand what the branch family went through," she said coldly. "They were slaves with no control over their own lives."
"Maybe," Boruto replied. "They were taught from birth to protect the main family—even at the cost of their lives."
At last, the three sisters found something they could jump into.
"So being an obedient puppet is what you call protection?" one of them mocked.
Boruto turned toward them and smiled.
But the smile in his eyes was old—far older than his age.
"Then what do you call serving the White Snake Sage and protecting Ryūchi Cave with your lives?"
"What's the difference between you… and caged birds?"
The three sisters fell silent.
There's a saying—a frog in a well.
When one's world is small, even comfort feels absolute.
From birth, you're told what your purpose is. You live for it. You die for it. And within that narrow world, you feel fulfilled.
War is never a child's game.
The Hyūga became the strongest clan in Konoha through their own ability. Even if they later declined, no one else had the right to judge them.
The Byakugan was the symbol of their strength—the bloodline limit everyone coveted.
On a battlefield, Hyūga would always be targeted for their eyes. The appearance of the Caged Bird Seal shattered those ambitions.
Once a branch family member was captured, death and eye extraction should have been inevitable. But the moment the host died—or was taken too far—the Byakugan was destroyed.
Thus, greed was cut off at the root.
For thousands of years, no one had ever broken the Caged Bird Seal.
The White Snake Sage said nothing, showing no anger at being used as a comparison. She simply watched Boruto, waiting.
"So you're saying," Boruto said slowly, "that the appearance of the Caged Bird Seal is tied to the Tenseigan?"
"Precisely," the White Snake Sage replied.
"Because the seal cannot be broken, it creates absolute control—and absolute protection."
Boruto's eyes widened as realization struck.
"Then… could it be that the Hyūga also gathered countless Byakugan, just like the moon clan, to create a Tenseigan?"
"Mm." The White Snake Sage nodded.
"No wonder," Boruto muttered.
"No one ever broke the Caged Bird Seal. And the Hyūga, who aren't known for fuinjutsu, somehow created something this absolute."
Everything suddenly fit together.
"Now that you know the reason," the White Snake Sage said calmly, "finding that eye shouldn't be difficult anymore."
"Of course," Boruto replied without hesitation. "Thank you, Grandma Sage."
He bowed once more.
This revelation alone was invaluable. Combined with the Ryūchi Cave Sage Mode, his strength had leapt to an entirely new level.
Now, some enemies he once had to treat with extreme caution…
He could finally face head-on.
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A/N: Advanced Chapters Have Been Uploaded On My Patreon
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