Kagerōza Inaba looked toward Gin Ichimaru. "What's this? Captain Ichimaru didn't introduce me?"
Gin Ichimaru narrowed his eyes, the corners of his thin lips curling upward. "I think it would be better for you to introduce yourself. Captain Aizen always loved moments like this. Moments when the lost are finally shown the truth."
"Ah... That's certainly true." Kagerōza Inaba adjusted his two-toned hair. "I am Kagerōza Inaba, 7th Seat of the 12th Division's Research and Development Institute. I serve as a section chief there, responsible for observing and researching the Dangai. Some call me the Dangai expert. But I have another identity. I was once the head of Soul Society's Project Spearhead, and the founder of Modified Souls."
Rangiku Matsumoto instinctively stepped back and looked helplessly toward Gin Ichimaru. "Gin...?"
"You realized it so quickly. Just what I would expect from a Lieutenant." Kagerōza Inaba nodded in satisfaction. "That's right. This Captain Ichimaru was created using Project Spearhead and Modified Soul technology. He is a Reigai."
Rangiku Matsumoto stared at Gin Ichimaru. "No... That's impossible... He..."
"He's giving off the same familiar Reiatsu, isn't he?" Kagerōza Inaba continued. "That is the brilliance of my research. By collecting a subject's Reishi and using it to create a Modified Soul, I can produce a Reigai identical to the original. Not only its appearance and Reiatsu, but even its Zanpakutō abilities can be perfectly reproduced. The same is true of its memories."
Rangiku Matsumoto immediately understood how dangerous such technology was. "What are you planning to do!?"
"What am I planning to do? No, no, no..." Kagerōza Inaba wagged a finger. "What I'm about to tell you is what I have already done."
Kagerōza Inaba was gradually beginning to savor the moment. Unlike the Shinigami of Seireitei, who remained oblivious to everything around them, he had worked day and night on this plan for years.
After nearly a century of preparation, his plan was finally on the verge of complete success. Everything had proceeded exactly as he intended, yet something had always felt lacking.
Seireitei was about to fall into his hands, but these Shinigami did not even understand how they had lost.
It left Kagerōza Inaba feeling as though he were wearing fine clothes in the darkness, with no one there to admire them.
"Back when I was still Ōko Yushima, everyone shunned me because my abilities were weak. Through Aizen's recommendation, I transferred from the 9th Division to the 12th Division and began working in technical development. On Central 46's orders, I improved the original Project Spearhead, eliminated its flaws, and developed the Reigai."
Kagerōza Inaba spoke at length, finally revealing everything he had kept buried in his heart with no one to confide in.
"But my research was too successful. So successful that Central 46 feared the Reigai might one day be used to rebel against them, so they terminated my research. The moment I received that news, I knew that, given Central 46's usual methods, my own fate would not be pleasant. So I made a brilliant decision!"
Kagerōza Inaba spread his arms, displaying the elaborate machinery behind him. Two cylindrical culture chambers were filled with an unidentified emerald-green liquid, and Nozomi Kujō was submerged in one of them.
"I split my Soul into two parts and altered my Reiatsu to escape Central 46's pursuit. One part took my research data and hid within the Dangai. The other assumed a new identity and joined the Research and Development Institute to study the Dangai." A sickly smile appeared on Kagerōza Inaba's face. "Those were painful, agonizing years, but I endured them. Through my research into the Dangai, I gradually recovered my old research data while waiting for an opportunity to obtain the Reishi of every Captain in the Gotei 13."
"Obtain their Reishi..." Rangiku Matsumoto recalled the Great Battle of Karakura Town. "You took advantage of that battle..."
"I contributed quite a bit to the development and use of the Tenkai Ketchū as well. I may not look it, but I am an outstanding member of the Research and Development Institute." Kagerōza Inaba continued his explanation. "I created Captain-level Reigai, but unless the Captains left Soul Society, the Reigai could never take their places. Then, as luck would have it, the 10th Division began carrying out a secret mission."
"As long as Momo Hinamori's Reigai stole the Ōin, Captain Hitsugaya would never return to Soul Society to report it. He would remain in the World of the Living and investigate alone in order to prove Momo Hinamori's innocence. The other Captains would inevitably be sent to the World of the Living to search for him. After that, the remaining Captains could be contacted individually and ordered to travel there in secret under the pretext of a covert mission. Every Captain would eventually enter the Dangai."
"My Raiku can manipulate space. It can copy not only enemies and their techniques, but even the Kōtotsu." Kagerōza Inaba spun Raiku in his hand. "With a little effort inside the Dangai, every Captain could be swallowed by the Kōtotsu."
"Do you have any idea what kind of disaster that could cause!?" Rangiku Matsumoto demanded. "With so many Captains missing, what happens if something goes wrong?"
"Then Soul Society will have no choice but to rely on my Reigai." Kagerōza Inaba pronounced each word clearly. "As things stand, Soul Society can rely only on me. Once I fuse with Nozomi Kujō, I will control all of Soul Society."
"You're delusional!" Rangiku Matsumoto glared at Kagerōza Inaba. "Muten is already in Soul Society. He'll destroy every one of your plans!"
"Muten Natsu?" Kagerōza Inaba sneered. "He's nothing more than a useless brat who hasn't improved at all."
...
"Bankai, Hihiō Zabimaru!"
Zabimaru expanded within a golden glow in Reigai Renji Abarai's hands. A continuous series of unnatural clicks rang out as a massive skeletal serpent head took shape. Countless beige bone segments extended behind it, forming a long skeletal serpent that coiled around his body again and again.
With a swing of the arm holding the Snake Tail Scepter, the skeletal serpent opened its jaws and lunged at Muten Natsu and Rukia Kuchiki.
They dodged simultaneously, and Muten Natsu charged straight toward Reigai Renji Abarai.
Rukia Kuchiki swung Sode no Shirayuki. "Some no mai, Tsukishiro!"
A circular pillar of ice surged between earth and sky, freezing several sections of the serpent's skeleton and restraining Hihiō Zabimaru's movements.
Muten Natsu seized the opening, closed the distance, and swung his blade at Reigai Renji Abarai's head.
Clang!
Ink spread through the air and blocked the approaching Zanpakutō.
Muten Natsu swept Myōki across in a lightning-fast Ink Fortress strike, but his opponent seemed to have predicted it in advance. The blade cut through empty air.
"You're much faster than you were back then." Reigai Takuma Tsunayashiro retreated to create some distance. "Muten, you've grown."
"Don't speak to me in his voice." Muten Natsu's gaze was cold. "Takuma is dead. The past I shared with him is not yours to desecrate."
"Desecrate...?" A trace of sadness appeared on Reigai Takuma Tsunayashiro's refined face. "Do you remember? That was exactly what you said to our teacher back then."
During his time at the Shin'ō Academy, Muten Natsu had been notorious for his laziness.
Sleeping in class was an everyday occurrence. If he could sit, he would never stand. If he could lie down, he would never sit.
Whenever they had to change classrooms, Takuma Tsunayashiro would carry the still-sleeping Muten Natsu on his back to the next room.
When their teacher eventually discovered this, Muten Natsu was unsurprisingly called in for a reprimand.
["You mustn't bully your classmate like that."]
["This isn't bullying. It's a friendship built on mutual trust."] Faced with the teacher's criticism, Muten Natsu argued with complete confidence. ["Don't desecrate the bonds of our friendship!"]
That had already been decades ago.
Reigai Renji Abarai swung his arm. Hihiō Zabimaru's bone segments separated on their own, discarding the frozen sections before reconnecting.
"Look at him carefully, Muten. What stands before you isn't some imitation. His Reishi has been resurrected through a Reigai. Don't you want to see Takuma brought back to life?"
"If he's Takuma brought back from the dead..." Rukia Kuchiki stepped beside Muten Natsu. "Then what are you?"
"I'm Renji Abarai!" Reigai Renji Abarai struck his own chest. "My body, my Reiatsu, and my Zanpakutō are all identical to Renji Abarai's. I am him!"
"Even if everything about you is identical, you're still a Reigai like him. You aren't Renji Abarai." Rukia Kuchiki turned her head. "Muten, what are you?"
"I..." Muten Natsu tightened his grip on Myōki. "I am myself."
"Correct." Rukia Kuchiki raised Sode no Shirayuki, her purple eyes bright and resolute. "So, what have you decided?"
Muten Natsu looked toward Reigai Takuma Tsunayashiro. "If you truly possess his memories, and if you really are just like him... then you wouldn't stand in my way."
"...That's true." Reigai Takuma Tsunayashiro lowered his eyes. "Go, Muten. I'll light the dawn for you. If I were the real Takuma, that's what I would say."
"Correct."
Muten Natsu stepped forward, and a cold flash followed.
"Hikotsu Taihō!"
Reigai Renji Abarai swung the Snake Tail Scepter. Powerful Reiatsu surged through the bone segments, growing stronger with every layer before erupting from the skeletal serpent's mouth. A crimson blast collided with the descending Myōki.
The sky darkened.
Amid a piercing shriek, the crimson blast was forcibly cleaved apart.
The enormous serpent skeleton shattered within the chaotic currents of Reiatsu. Its individual bone segments could no longer remain connected and scattered in every direction.
Muten Natsu took another step. His Hell Armor changed from pitch black to deathly white, and the power stored within it erupted. A chilling blade of light unfurled behind him like a banner.
Reigai Takuma Tsunayashiro raised his Zanpakutō. "Shine forth, Dawn!"
The Zanpakutō in his hand suddenly turned pitch black, as though it had absorbed every trace of light. At the same time, a brilliant rainbow glow appeared across Muten Natsu's body.
This was the Shikai Takuma Tsunayashiro had honed through the elite education of the nobility. By concealing his own Reiatsu, he could perceive his opponent's Reiatsu more clearly, locate their weaknesses, and render all their defenses ineffective.
Wherever the rainbow light pointed, no form of defense had any meaning.
"Higa Zekkō!"
Reigai Renji Abarai roared and swung the Snake Tail Scepter. The serpent bones scattered around Muten Natsu rose into the air and formed ring after ring around him. An ominous red light flared as they stabbed toward him from every direction at once.
"Tsugi no mai, Hakuren!"
From outside the encirclement, Rukia Kuchiki swung her blade and released a wave of freezing air. An ice wall formed beside Muten Natsu, shielding him.
The rainbow light passed effortlessly through the ice and guided Reigai Renji Abarai's attack.
The sharpened serpent bones pierced the ice wall and struck Muten Natsu's body.
In the next instant, Muten Natsu's attack tore through both Reigai.
"How...?" Reigai Renji Abarai stared in disbelief at Muten Natsu, who had suffered only minor injuries. "But I clearly..."
He could understand why the other serpent bones had failed to inflict any serious damage.
But even the bone guided by the rainbow light had failed to leave a fatal wound. Something was clearly wrong.
Reigai Takuma Tsunayashiro's gaze shifted. "The ice... I see. It refracted the light."
The ice wall created by Rukia Kuchiki's Hakuren had never been meant to block the attack. Its purpose was to refract the rainbow light and throw the attack off course.
"Muten..." Reigai Takuma Tsunayashiro slowly began to fade as he looked at Muten Natsu standing before him. "Do you no longer need me to light the dawn for you?"
"Don't desecrate the past we shared." Muten Natsu's eyes shone with unwavering resolve. "The dawn he lit for me has never gone out."
The Reigai gave a graceful chuckle, his eyes flickering. "So I really am not him..."
The last traces of him vanished.
Muten Natsu tightened his grip on Myōki and looked toward the Research and Development Institute.
Boom!
Using the underground passage to avoid the Research and Development Institute's guards, Muten Natsu and Rukia Kuchiki broke directly into Kagerōza Inaba's secret laboratory.
The enormous chamber was filled with massive, intricate machinery connected by a dense network of pipes and wires. Two cylindrical culture chambers held an unidentified emerald-green liquid. Nozomi Kujō floated inside one, while Kagerōza Inaba floated inside the other.
Glass shattered with a sharp crack.
Myōki smashed through the culture chamber and pierced Kagerōza Inaba's chest.
"Guh!" Kagerōza Inaba spat out a mouthful of blood. His open eyes were filled with undisguised delight. "Muten Natsu, you came here exactly as I expected. But you came to the wrong place! Hahahahaha!"
...
"Hahahahaha!" Kagerōza Inaba threw back his head and laughed. "I can feel it. Muten Natsu has already destroyed the Reigai I prepared for him!"
Someone capable of creating Captain-level Reigai could naturally create one of himself.
The Kagerōza Inaba who had previously gone to the World of the Living had been that Reigai. Its purpose was to mislead the pursuers who followed the trail of Reishi back to Soul Society.
"The Muten Natsu you placed so much faith in has already gone the wrong way." Kagerōza Inaba rubbed his face until he regained his composure, then gave Rangiku Matsumoto a restrained smile. "And after speaking with you for so long, I have adjusted my condition enough to begin the fusion."
Kagerōza Inaba raised Raiku. "You're no longer of any use."
"Then let me..." Gin Ichimaru pressed down on Kagerōza Inaba's Raiku. "...kill her."