The elder carefully placed Hinata Haruki onto the bed… Ahem—don't get the wrong idea, he certainly wasn't taking off any clothes. Elder Sō gently smiled.
"Child, I'll give you a gift today—as a celebration for your seventh birthday."
He carefully opened the container holding the Byakugan, wrapping Nisshin's eye in a soft glow of green chakra. The chakra surrounded the Byakugan, making it float gently between his fingers. With his other hand, he lifted Haruki's eyelid, revealing the sealed eye beneath. Then, he placed Nisshin's Byakugan over Haruki's.
"Yin–Yang Release: Fusion Technique!"
The green light in his hand flared brightly, a torrent of chakra flowing into Haruki's eye. Nisshin's eyeball began to change, slowly sinking into place as it melded with Haruki's. The optic nerves, retina, vitreous body, lens, and cornea fused one by one. Haruki's damaged optic nerve was repaired by Nisshin's, and the injured areas of the eyeball rapidly regenerated.
At the same time, Haruki's Byakugan seemed… different. It felt purer—brighter, more vibrant—emitting a serene, untainted aura. Compared to his other Byakugan, one now appeared dull while the other shone brilliantly, its capabilities and visual prowess far stronger.
Nisshin's eye vanished completely into Haruki's, transforming it into what Elder Sō called the Pure Byakugan.
Taking a slight breath, Elder Sō repeated the process with Nisshin's other eye. Soon, both of Nisshin's Byakugan were gone, fully fused into Haruki's.
At that moment, the Caged Bird seal on Haruki's forehead glowed, attempting to suppress the power of his newly reborn Byakugan.
"Hmph! A mere curse seal dares to shackle the Prince of the Byakugan? You'll have to contend with the body of the Sage himself first!" Elder Sō snorted coldly and withdrew an ancient scroll from his robe.
"Release! Release! Release!"
One by one, the three seals upon the scroll were undone with different techniques, revealing something extremely precious inside. When the scroll was fully unfurled, it displayed an intricate black sealing array, with a large "Seal" character at its center.
Green chakra burned in Elder Sō's palm as he pressed it into a designated handprint mark within the array.
"Forebears… today, I will fulfill the mission you entrusted to us!"
The chakra flowed from his palm, tinting the seal marks green, until an ancient vial emerged from the scroll's release. Elder Sō carefully caught it, slowly uncorked it, and, with his green chakra, levitated its contents into the air.
It was a small clump of fresh, crimson blood.
"This is the blood of our ancestor—accept this precious gift! Yin–Yang Release: Fusion Technique!"
Without pausing the fusion process, Elder Sō's chakra surged even more fiercely. The blood was wrapped in green chakra and floated toward Haruki.
This drop of blood radiated immense vitality and carried a faint, luminous green chakra. The instant it neared Haruki, it reacted—its chakra pulsated actively, resonating with the faint blue chakra in Haruki's body. The resonance caused Haruki's chakra to flow outward from his tenketsu points, becoming vibrant and energetic.
Elder Sō wasn't surprised—he simply smiled faintly. Suddenly, he crossed both hands and pressed them firmly onto Haruki's chest.
"Mmm!" Haruki's brow furrowed as he let out a muffled groan.
The green chakra from the blood surged into Haruki's body, fusing into his skin along with its immense vitality and the pure bloodline of the Ōtsutsuki. Guided by the blood's energy, Elder Sō's own green chakra poured into Haruki as well.
Inside Haruki's body, not only did his chakra resonate with this power, but the bloodlines of Hamura and Hagoromo Ōtsutsuki within him also responded joyfully, welcoming the new energy. Under the effects of Yin–Yang Release, these powers began to merge.
Haruki's blue chakra instantly blended with the emerald green chakra, turning entirely into that vibrant green. It glowed with the vitality of life itself, wrapping his body in a protective aura. The blood then seeped fully into Haruki's skin, disappearing within him.
His body began healing at astonishing speed—fractured leg bones fused together, internal organs regenerated, muscles mended, and skin wounds vanished. Even his physique became sturdier and more resilient.
Then, gray magatama markings appeared on the skin around his shoulders and neck, becoming sharper until they were clearly visible. These magatama matched those of Hamura Ōtsutsuki, though Hagoromo's were black while Haruki's, like Hamura's, were gray.
The emerald chakra now surged toward the Caged Bird seal on Haruki's forehead. The seal glowed green in resistance—but it was no match for the chakra of a Sage's body. Like an eraser, the green chakra gradually rubbed away the "卍" symbol, breaking the curse seal apart until nothing remained.
Even then, the transformation wasn't over. The green chakra flowed into Haruki's Byakugan, triggering a mutation. The usual bulging veins beside his eyes receded, the grayish patterns in his pupils vanished, and the pure white color changed.
Emerald chakra flooded the pupils, tinting them a pale blue, with the iris deepening into a rich navy hue. Around the pupil, a ring of bright silver formed—like the sun's corona—casting a faint radiance. His eyes now shone with an almost hypnotic beauty.
This was the legendary evolution of the Byakugan—the Tenseigan.
Most of Haruki's injuries had already healed. Elder Sō finally ceased channeling chakra, collapsing to the side, breathing heavily. The green chakra faded into Haruki's body, and the magatama markings on his shoulders sank beneath the skin, vanishing.
As the chakra left his pupils, the deep blue eyes gradually returned to their normal Byakugan state.
The Yin–Yang Release: Fusion Technique harnessed the power of creation to perfectly merge two kindred elements—enhancing strengths, eliminating weaknesses, and creating something greater. The Ōtsutsuki had once used this method to combine countless Byakugan into the clan's greatest treasure—the Great Tenseigan.
By merging the Pure Byakugan with Haruki's, Elder Sō had repaired and purified it beyond even Nisshin's. The purity of a Byakugan depended not only on bloodline but also on the chakra infused into it—and Haruki's chakra was far purer, stronger, and warmer than Nisshin's. Under the fusion's effect, the Byakugan had undergone another purification.
Then, through the ancestor's blood, Elder Sō granted Haruki the Sage's Body of the Ōtsutsuki, merging it with his existing Senju and Hyūga bloodlines. This perfect compatibility allowed the fusion to succeed without rejection—far more seamlessly than Uchiha Madara's forced implantation of Hashirama's cells or Kabuto's grotesque grafting of countless corpses' DNA.
Now, Haruki bore the blood of the Hyūga, the Senju, and the Ōtsutsuki—effectively inheriting the legacies of Hamura, Hagoromo, and even much of the legendary Kaguya Ōtsutsuki herself. Combined with the Sage's Body and Pure Byakugan, Haruki's eyes had evolved into the Tenseigan.
"The fusion… succeeded… Haha! Cough, cough! Ancestors, I have fulfilled your mission!"
Elder Sō's voice was weak, his face aged further—but his expression brimmed with joy.
"I felt the power of the Tenseigan just now… But Haruki is still too young. The Sage's Body has only just formed—it hasn't matured… Neither the Tenseigan nor the Sage's Body can yet show their true strength. Hm… This newborn Pure Byakugan will also need training… Cough!"
He covered Haruki with a blanket, closing the boy's eyes, then rested his own head upon the stone table.
Meanwhile, deep inside the Moon's inner world, in the colossal palace at the heart of its artificial sun…
The sun-like construct trembled violently for several minutes before stabilizing. An elderly man with gray-white hair and a half-draped ceremonial robe opened his eyes. Around his neck was a ring of gray magatama, and on his back, his robe bore the crest of a large crescent moon encircling a small circle.
"What was that just now…?" he murmured.
"Father! The Tenseigan just experienced some kind of disturbance!"
Another man, similarly dressed and gray-haired, entered hastily.
"How strange… What could have happened?" the elder pondered.
"Father, could this be related to the villain who stole the Demonic Statue of the Outer Path?"
"That statue was sealed within the Moon—it was safe. No outsider can reach the Moon, let alone break the seal-stone guarding it. And our Ōtsutsuki clan has watched over it for generations. No ordinary person could ever steal it.
"There is only one way—the descendant of our forebear, the Sage of Six Paths Hagoromo—someone with the Rinnegan—could summon it away from inside the Moon. When the statue was stolen before, the Tenseigan showed no reaction. This disturbance should have nothing to do with that thief."
"Tch… We still haven't found the culprit! For a descendant of Hagoromo to commit such a crime… Once that statue is loosed, the world below will again be drenched in blood! The ninja of the Earth have strayed too far!" the younger man said through gritted teeth.
"Keep investigating. When this war ends, we'll go to Earth quietly—don't alert anyone. How fares the war?"
"It seems to be nearing its end… though who knows if there will be another."
"There will always be another… Let us hope they turn from their path. Otherwise, we will have to use the Tenseigan… to bring about the world's end."
The elder closed his eyes, and the younger bowed deeply before retreating in silence.