But Unohana Retsu had nothing to do with the 11th Division anymore, and hardly anyone knew she had been the First Kenpachi. She couldn't possibly say something like that to their faces.
She continued teaching Natsuki some Kaidō.
Unohana Retsu assessed Natsuki. "Your skill in Kaidō is almost on par with mine. There isn't much more I can teach you."
"Captain Unohana, you're too kind. You're the captain of the 4th Division. I don't think I could reach your level after such a short time studying."
"Besides, as a veteran captain, you must know more than just Kaidō."
"So, Captain Unohana, there's plenty you can teach me."
Natsuki looked at Unohana Retsu earnestly, like a diligent student eager to learn from his teacher.
Feeling Natsuki's gaze, Unohana Retsu was momentarily taken aback.
She couldn't help thinking of Gosu Kenpachi again.
Like Kyoraku Shunsui, she didn't think Gosu was fit to become the new Kenpachi. She had once told Natsuki that the Shinigami of the 11th Division often came to the 4th Division for treatment because they frequently got injured in battle. The two Divisions were close and knew each other well.
As the former lieutenant of the 11th Division, Gosu was naturally familiar to Unohana Retsu.
She knew exactly how strong he was.
The Kenpachi before Gosu, Azashiro and Kuruyashiki, had both been undeniable powerhouses.
Gosu alone was not.
Back then, she had stepped down from the position of First Kenpachi, leaving behind a succession ritual unique to the Kenpachi: only the one who defeated the previous Kenpachi could become the new one. Her purpose was to ensure that each new Kenpachi would be stronger than the last.
Each generation stronger than the one before. Sooner or later, a formidable warrior would appear who could truly impress her.
Unohana Retsu had established this tradition not to cultivate powerful warriors for the Gotei 13, but to find an opponent she could fight and enjoy the thrill of battle with.
In her heart, she already had someone in mind.
She had learned Kaidō and voluntarily stepped down as the First Kenpachi for one reason: to wait for that person.
She looked forward to his arrival in Seireitei.
Of course, if another master capable of fighting her appeared before then, that would be a good thing, too.
Kuruyashiki Kenpachi was strong, but he still fell a little short for Unohana Retsu.
Azashiro Kenpachi had defeated Kuruyashiki and was undoubtedly even stronger, but she had never had the chance to witness Azashiro's strength.
If the tradition had continued as intended, each successive Kenpachi would have grown stronger, until the person she awaited finally appeared.
But no one could have expected that a powerhouse like Azashiro Kenpachi would be the last of his kind.
The position of Kenpachi had fallen to Gosu.
That meant that even if a Shinigami eventually defeated Gosu and became the new Kenpachi, there was no guarantee he would be as strong as Kuruyashiki or Azashiro. She would have to wait many more years.
Whenever she thought about it during this time, Unohana Retsu couldn't help feeling a little vexed.
At this moment, after hearing Natsuki's words, for some reason, she suddenly thought of it again.
Then Unohana Retsu looked at Natsuki.
"Is there something on my face, Captain Unohana?" Natsuki asked, puzzled by her gaze.
Unohana Retsu didn't answer. Instead, she asked in a low voice, "Do you want to learn Zanjutsu?"
Natsuki's eyes immediately sharpened.
He knew quite a bit about Unohana Retsu.
The First Kenpachi was said to have mastered every sword art and style of swordsmanship, which was why she was also known as "Yachiru." The name meant "eight thousand styles," with eight thousand being a figurative number that represented infinity. In other words, Unohana Retsu was the most knowledgeable person in Soul Society when it came to swordsmanship and Zanjutsu.
The Zanjutsu she meant was completely different from the kind taught at Shino Academy.
"Captain Unohana, you want to teach me Zanjutsu?" Natsuki quickly caught on and asked.
Unohana Retsu replied, "As you said, I'm a veteran captain, and I've learned quite a few things. Aside from Kaidō, Zanjutsu is the only other skill I can offer to teach you. If you're willing, I can give you some pointers."
"That would be wonderful, of course." An opportunity to grow stronger was right in front of him, so Natsuki wouldn't turn it down. He had said those things earlier in the hope that Unohana Retsu would guide his training.
Most people only knew Unohana Retsu as the kindhearted captain of the medical division, someone unsuited to battle.
But Natsuki knew she could fight better than 99 percent of the Shinigami.
She was one of the best fighters in the Gotei 13.
And so, alongside his Kaidō lessons, Natsuki began studying Zanjutsu under Unohana Retsu in the 4th Division.
Natsuki was surprised that Unohana Retsu was teaching him Zanjutsu.
Unohana Retsu's reasoning was simple.
Since something had gone wrong with the Kenpachi succession and the position had fallen into the hands of a weakling, she, the First Kenpachi, couldn't simply stand by. She didn't mind personally nurturing a powerful warrior to take the position of Kenpachi.
Natsuki often came to study Kaidō with her, so she had seen his talent for herself.
To determine whether a Shinigami could become powerful, their control over spiritual power and their talent for Kidō were secondary factors.
The most important factor was their Reiatsu.
Reiatsu determined a Shinigami's potential.
The stronger their Reiatsu, the farther they could go.
While teaching Natsuki Kaidō, Unohana Retsu had naturally sensed his Reiatsu.
It was powerful.
When she had first taught him Kaidō, her estimate of his spiritual power had been around the fourth class. Now it should be at the third.
The fourth class was already enough to qualify someone as a lieutenant.
The third class was the level of spiritual power possessed by a captain in the Gotei 13.
It might have seemed like a difference of just one class, but there was an enormous gap between the top three classes and the ones below them. Natsuki had broken through that barrier and reached the third class in such a short time. It was truly astonishing.
Of course, that wasn't the main reason Unohana Retsu thought highly of Natsuki. Most importantly, his spiritual power was still growing. The third class wasn't his limit. If he kept growing, even she had no idea how powerful he might become.
She also knew about Natsuki's past.
Even counting the years he had spent in Hueco Mundo, he had only been a Shinigami for as long as it had taken him to graduate from Shino Academy.
He was a genuine genius.
And a genius like him had never even received the Academy's instruction, which only confirmed that Natsuki was an uncut gem.
Nothing was more gratifying than personally shaping an uncut gem into something extraordinary.
Especially when doing so could also satisfy her own selfish desire.
Before you continue