Fear  

Synchronization was an ability granted to Ailin by his "Innate Domain: Unlimited Blade Works."

This ability allowed him to analyze a wider range of objects, deepening his understanding of them.

After all, "Unlimited Blade Works" could replicate things beyond just swords.

However, the replicated items were always one level lower than the originals.

But in the world of Bleach, where "anything could become a Zanpakutō ability," as long as Ailin designated a particular ability as a Zanpakutō's Shikai or Bankai, its power wouldn't decrease after it was created.

After successfully synchronizing with an object, Ailin could obtain all its information.

This included, but was not limited to, "shared growth experiences," "replication of years of accumulation," and so on.

When Ailin used "Synchronization" on a Zanpakutō, he could forcibly seize its control.

After deciding to teach Aizen a lesson, Ailin had used "Synchronization" to take control of Sōsuke Aizen's Zanpakutō, Kyōka Suigetsu, inheriting everything Aizen had left behind.

Now, Ailin employed the same method, wresting control of Senbonzakura from Byakuya Kuchiki.

As Byakuya watched in horror, Ailin held Senbonzakura upside down, then released his grip.

"Bankai – Senbonzakura Kageyoshi!"

The released Senbonzakura fell straight down. As its blade touched the ground, transparent ripples spread outward, engulfing the entire blade.

After Senbonzakura was completely swallowed by the spatial ripples, dozens of ripples formed two rows, extending outwards on either side of Ailin.

The next moment, enormous blades rose from each ripple.

Each blade was about forty centimeters wide and over five meters tall.

Then, starting from their tips, the blades transformed into countless cherry blossom-colored petals, swirling and dancing around Ailin.

Boom!

Under Ailin's control, a tidal wave of cherry blossom petals surged towards Byakuya.

Shhh, shhh, shhh…

Crimson blood splattered on the countless petals.

Against Senbonzakura's Bankai, Byakuya was utterly powerless. He was instantly swallowed by the wave of petals, his body swept away by the surging tide.

When the cherry blossom wave receded, Byakuya lay before Ailin, his entire body drenched in blood.

He swayed unsteadily, then collapsed.

Byakuya's body was covered in wounds.

Blood poured from his injuries, forming a pool on the ground.

"Byakuya, if I were an enemy of the Kuchiki clan or Seireitei, what could you do now?" Ailin asked, stepping on the countless cherry blossom petals, his figure like a lone boat amidst a sea of blossoms.

What could he do?

Byakuya's mind went blank for a moment.

He was the head of the Kuchiki clan, a role model for all nobles in Seireitei.

He was also the captain of the 6th Division, a member of the Gotei 13 tasked with protecting Seireitei.

Safeguarding Seireitei was his duty.

But…

If Uncle Ailin was truly an enemy, then all he, who had fallen at his feet, could do was pray for a more powerful ally to arrive before his death, entrusting all his hopes to someone else.

And what if there were no reinforcements?

This question filled Byakuya with a fear even greater than having his Zanpakutō stolen.

The countless cherry blossom petals dispersed, returning to Senbonzakura's main body.

Clang!

Ailin stabbed Senbonzakura into the ground beside Byakuya and said in a disappointed tone, "Byakuya, you've truly disappointed me. Although Senbonzakura's Bankai is quite impressive, I didn't use more reiatsu than you to activate it.

With your strength, even if you can't defeat Senbonzakura's Bankai at that level using Zanjutsu, Shunpo, or Kidō, you shouldn't have been defeated so quickly.

Does losing control of your Bankai, seeing someone else using it against you, truly fill you with such fear?"

With those words, Ailin bent down, grabbed the Kenseikan holding Byakuya's hair in place, and yanked it off.

"Over the years, you've become far too complacent because of Hisana. With your current strength, I find it hard to believe that you can represent the Kuchiki clan and protect Seireitei in the future.

I will temporarily hold onto this Kenseikan, the symbol of your status as a high-ranking noble of the Kuchiki clan.

If you want to regain your pride, train hard and challenge me. Take back your Kenseikan from my hands!"

…

The scenery shifted. Rukia blinked, and the world of countless swords vanished. The familiar cherry blossom tree and surrounding buildings told her she had returned.

She glanced at Captain Byakuya. His injuries had completely healed, and even his Shihakushō and captain's haori were restored to their original condition.

If not for his slightly disheveled hair, now hanging loose without the Kenseikan to hold it in place, Rukia would have doubted whether everything she had just witnessed was merely a dream.

Before Byakuya, a golden spatial ripple appeared. Ailin released the Kenseikan he had taken from Byakuya, letting it fall into the ripple.

Byakuya didn't say a word as he watched Ailin's actions.

He drew Senbonzakura from the ground, sheathed it, and left the courtyard.

In his mind, Byakuya evaluated his performance in the fight against his uncle.

After replaying those few brief moments of combat over a dozen times, the score he gave himself made his face burn with shame.

Zero!

Knowing the gap in strength between himself and Uncle Ailin, he hadn't used Shunpo to evade his uncle's attack but instead drew Senbonzakura to block. How arrogant he had been!

Furthermore, as Uncle Ailin had said, when he lost control of Senbonzakura, seeing his uncle using its Bankai against him, his fear had overwhelmed him, and his performance had been abysmal.

As Uncle Ailin had pointed out, whether it was Shunpo, Zanjutsu, or Kidō, he could have effectively blocked Senbonzakura's attacks.

But he had done nothing, ultimately allowing countless blades to pierce his body, leading to his defeat.

Unconsciously, Byakuya arrived at the outskirts of Rukongai, the place where he had met Hisana.

This was also where he had practiced Zanjutsu, Hakuda, Hohō, and Kidō in the past.

However, he hadn't been here since marrying Hisana.

"Hisana… Uncle Ailin was right. I've become too complacent. And I rely too heavily on Senbonzakura. I can continue to refine my control over Senbonzakura, but I cannot neglect training in other areas… Senbonzakura enhances my upper limits, but the four basic Shinigami skills…"

Tearing a strip of white cloth from his captain's haori, Byakuya tied it around his head as a headband.

If Ailin saw him now, he would notice the striking resemblance to Byakuya's appearance during the Thousand-Year Blood War.

Of course, the headbands couldn't be compared.

Byakuya's current headband was just a torn piece of his captain's haori. The headband he wore during the Thousand-Year Blood War was no less expensive than Kazeshini no Yoroi or the Kenseikan.

Those were luxury items, each worth several mansions in Seireitei.

…

Ailin watched Byakuya leave, saying nothing more. He had already said what needed to be said. Ever since Byakuya met Hisana, he had devoted all his energy to her, neglecting his training.

In twelve years, his strength hadn't regressed.

After all, Byakuya was still in a period of rapid growth. Even without much training, his reiatsu was increasing.

However, compared to twelve years ago, Byakuya's improvement had been minimal.

If his past self were to fight his current self, the outcome would be a toss-up.

Twelve years ago, Byakuya had ingrained the four basic Shinigami skills into his "instincts," possessing the ability to challenge opponents stronger than himself.

Twelve years later, his "instincts" had dulled, but his reiatsu was stronger than before.

Ailin wouldn't be surprised no matter which one emerged victorious.

Although this blow to Byakuya had been harsh, Ailin believed he would recover.

After all, for Byakuya Kuchiki now, his noble pride and the responsibilities of the Kuchiki clan were paramount.

Now that Ailin had shown him his weakness, to prevent a repeat of his defeat in Unlimited Blade Works in the real world, Byakuya would undoubtedly pull himself together.

"Teacher Ailin, is Captain Byakuya alright?"

However, compared to Ailin, Rukia was far more worried.

The battle between Captain Byakuya and Teacher Ailin was a mirror image of her own fights against Byakuya.

No, not a mirror image!

To be precise, the battle between Teacher Ailin and Captain Byakuya was a downgraded version of her fights against him.

When she sparred with Captain Byakuya, she could at least withstand a few blows. She wouldn't be instantly defeated.

Of course, Rukia knew that she could only survive a few moves because Captain Byakuya had suppressed his speed, strength, and reiatsu to match her level.

But in the fight between Teacher Ailin and Captain Byakuya, there was no holding back.

The speed was so fast that Rukia could only hear the sonic booms, unable to even see their figures.