"What do you mean by that?" Ukitake asked, his tone no longer light.
Shin answered calmly:
"Something extraordinary must've happened to your body, Captain Ukitake. Am I right?"
Ukitake said nothing. The casual air he'd worn a moment ago vanished, replaced by solemnity and quiet weight.
Shin continued:
"To be blunt—your lungs aren't the lungs of a man who's lived over a century. They resemble those of a three-year-old child."
Unohana had said the same.
Ukitake turned toward Shin, finally seeing him not as some junior seated officer, but as something far more dangerous and perceptive.
"What were you implying before? That you can actually heal it?"
"It's worth a try," Shin replied. "But if I succeed, there might be… other complications. A child's lungs can't properly support an adult body. Still, those are issues we can manage. What I need to know is this—if I could help you completely 'rid yourself' of this illness, would you want that?"
Ukitake fell silent.
He had lived with his condition for so long it had become a part of him. He knew it wouldn't kill him, but it betrayed him often—at critical moments when he most needed to stand tall as captain of the 13th Division.
What did Shin mean by 'completely rid'?
Could he have uncovered the truth?
That his lungs weren't his own—but a divine gift from Mimihagi, the One-Eyed God?
The Right Arm of the Soul King… to whom his body was bound.
"Shin-kun, you…"
Ukitake opened his mouth, but thought better of it, swallowing the question.
He sighed.
"Seems you've seen more than I thought… I need to consider this carefully."
Shin nodded.
"Let me know when you've made up your mind."
He bowed, turned, and left the room.
Outside, Shiba Kaien immediately approached.
"Well?"
"Still needs preparation," Shin replied.
"So… you can heal him?"
"Possibly."
Shin wasn't making promises. If Ukitake refused the treatment, no one could blame Shin for failing where even Unohana hadn't succeeded. His reputation would remain intact.
Two days later, Ukitake paid a personal visit to the 4th Division.
He wasn't alone—accompanying him were Vice-Captain Shiba Kaien, 8th Division Captain Kyōraku Shunsui, and Vice-Captain Ise Nanao.
Kotetsu Isane received them at the entrance.
"Is there something urgent, Captains?"
Ukitake smiled.
"I'm here to see Tachikawa Shin. I've decided to undergo treatment."
"Treatment?" Isane blinked in confusion.
"Oh? Looks like dear Isane-chan hasn't heard the news," Kyōraku said with a chuckle, addressing her with familiar fondness.
Just then, Unohana appeared, Shin walking behind her.
"What rare guests," she greeted warmly.
Kyōraku instantly straightened up, his playful expression sobering.
"Captain Unohana."
Ukitake asked:
"I assume you've been informed?"
"Shin told me everything," she replied with her usual calm smile.
Among them, only Isane seemed completely in the dark. Her gaze darted repeatedly to Shin.
"Captain Unohana, if I may ask," Kyōraku began, "might we trouble you to assist? Just in case."
It was a polite way of asking her to act as backup. When it came to healing, no one in Seireitei matched her.
"Isane, prepare a medical room."
"Yes, ma'am!" she said quickly and hurried off.
Kyōraku now turned to Shin. They had seen each other before—at the Shin'ō Academy's cultural festivals—but had never spoken directly. He had heard plenty about the young genius from others.
"Tachikawa," he asked, "how confident are you about this? Can you guarantee there won't be any unforeseen consequences?"
If it had been a normal illness, he wouldn't have asked. But Kyōraku knew the truth about Mimihagi too. He shared Ukitake's unease.
Shin tilted his head slightly, smiling.
"Captain Kyōraku, asking me to guarantee the future—that's a bit much, isn't it?"
Ukitake chuckled.
"It's just a treatment. I've had many before. Worst case? It doesn't work."
Shin failing wouldn't mean anything—only that he was no different from any other healer.
"Alright," Kyōraku sighed. "We'll leave it to you, then."
Isane soon returned.
"The room's ready."
The group followed her to the medical chamber.
"Do you need anything else?" Kyōraku asked.
"Only myself and my captain will be performing the treatment," Shin said. "Captain Ukitake just needs to be ready."
Only now did Isane begin to understand—Shin was going to attempt to heal Ukitake's incurable lung condition. A condition even Captain Unohana had failed to mend.
When had Shin…?
And why hadn't she heard about this?
Then she remembered—she'd been avoiding him all this time.
As she drifted into her thoughts, they reached the chamber. Shin turned back and said:
"Please wait outside."
Kyōraku, Nanao, Kaien, and Isane all remained in the corridor.
Inside, only Shin, Unohana, and Ukitake remained.
"How's this going to work?" Ukitake asked, eyeing the room. It looked nothing like the treatment chambers he was used to.
"With my Zanpakutō," Shin replied. The usual medical tools were useless.
"Then I'll leave myself in your hands," Ukitake said, beginning to unbutton his robes.
"Please sit comfortably on the floor," Shin added.
Ukitake complied, bare-chested, cross-legged, composed.
Shin looked to Unohana.
"Captain, I won't need your help during the treatment itself. But if I succeed… his body might react unpredictably. That's when I'll need you."
Unohana nodded silently.
"If I fail..." Shin paused. "There shouldn't be any lasting harm."
Ukitake nodded as well, giving them his full trust.
Shin stepped behind him.
He didn't draw the asauchi at his waist.
Instead, before Unohana's eyes, he lifted his hand and shaped it as though gripping a hilt—
—and light bloomed across his arm.
A blade appeared in midair, materializing from pure reiryoku.
Unohana's eyes widened.
She hadn't even seen how it had formed—only that suddenly, it was there, gripped in Shin's hand.
The sword's design was stunning: the scabbard pitch black, etched with vivid red spider lilies—higanbana, the flowers of the other shore. Crimson ribbon coiled around the sheath, and the tsuba too was red.
It was beautiful and ominous.
Unohana glanced once more at the plain asauchi at Shin's waist.
Then back at this new blade.
This was his true Zanpakutō.