In the end, battles between Shinigami are battles of spiritual pressure. No matter how overwhelming the ability or concept, it must be backed by sufficient reiatsu to be truly effective.
Though what stood before him was the Right Hand of the Soul King, it had long since been bound to Ukitake's body, functioning in symbiosis. Earlier, Shin had made Ukitake release the majority of his spiritual pressure precisely to weaken that right hand's power.
Without that, he never could've restrained it so easily with his Zanpakutō's abilities.
Now aware that it was bound within Shin's rule, the black hand turned violent. Tendrils of tar-like substance surged from its form, hurling themselves against the spirit barrier and toward Shin.
But every movement ended the same—it would jerk forward, lash out—and then regress, caught in a loop, always pulled back to its starting position.
Over and over again, it fought.
And over time, its strength dwindled.
Shin maintained his focus, watching as the spirit barrier reconfigured—splitting in two. One half surrounded the hand alone, sealing it off from Shin.
Then Shin manipulated the barrier to gently pull the hand down to the ground.
The massive eye on its back locked onto him, still burning with malevolence—but it had no power left to resist.
Shin stood still, thoughtful.
The safest choice would be to keep it sealed and hand it over to the Thirteen Court Guard Squads, wash his hands of it.
But if he did that… would all this have been for nothing?
Slowly, he stepped forward.
Staring down the writhing hand, he raised his own—and reached into the barrier.
At once, the black mass lunged, clawing toward his arm like a starving beast.
A rush of vertigo consumed him.
When his vision cleared, he was no longer in the room.
He stood in a white-lit space, the floor beneath him a shallow pool of water.
A short distance ahead, the hand now appeared more… human. Still monstrous—its five fingers clenched tight, the eye on its back wide open—but it was no longer made of black tar. It had flesh. Bone. And it wore a flowing white robe and trailing ribbons, as if it had descended from some divine realm.
It felt less like an enemy, more like… a remnant of something ancient. Powerful.
But still indifferent.
The eye stared at him—not with hatred, but with deep, unfeeling detachment.
Shin raised his hand, inspecting it. Lowered it again.
Black fluid began to spread across the water's surface, rising from beneath the entity and crawling toward him like living ink. It coiled around his feet, his legs, climbing higher—until it had engulfed him entirely, forming once again the shape of the black hand around his body.
And then—
It peeled away.
It slipped off his body like molted skin, returned to the water, and slithered back toward the being.
"It's useless now," Shin murmured. "In your current state… you're bound to me."
Back in the medical room—
Shin's eyes snapped back to clarity.
He sheathed the white dagger—Tōtai, Regression—and instead drew the asauchi always at his waist. Calmly, he plunged it into the spirit barrier.
The black substance surged toward it immediately, swallowing the blade, coiling around it like a parasite.
Then—
A flash of light.
The black tar was gone.
As if it had been converted into spirit particles and absorbed.
Clack.
The asauchi dropped to the floor, apparently unchanged.
Shin covered the blade with Higan's power—his red Zanpakutō—sealing it within the concept of stasis, before picking it back up and sliding it into its sheath.
Behind the barrier, Unohana had witnessed only fragments. She saw the black hand. She saw the moment the barrier dropped—and then it was gone. Vanished without a trace. She had no idea what had actually occurred.
As for Ukitake, his condition had been stabilized.
His lungs still resembled those of a three-year-old child, and they were riddled with disease—but now, with that foreign entity removed, Unohana could begin proper treatment.
"Captain," she called softly.
"It's done?" Unohana asked.
"More or less." Shin nodded. "Ukitake-taichō can now be healed. If I'm right, we'll need you to first purge the illness from his lungs completely—then have the Twelfth Division administer a reagent to accelerate organ growth."
The illness had always been serious—but for the Fourth Division, it was no longer insurmountable. The tragedy had been Ukitake's upbringing: raised in the Rukongai, lacking proper treatment, his parents had turned to divine prayers.
Now Unohana had seen it with her own eyes: the black hand, the root of his disease, was gone.
When Shin and Unohana stepped out of the medical chamber, the others were waiting anxiously—Kyōraku, Kiyone, Ise, Yamada, and more.
They didn't say anything.
Just looked at him, eyes wide.
Shin kept quiet for a beat… and then smiled.
"It's done."
Shiba Kaien stepped forward and, flustered, gave Shin a playful punch in the chest.
"You bastard! Why the hell would you keep that face on!?"
He peeked inside the room, saw the still figure on the bed, and his expression softened.
"I mean… damn. Shin, seriously—thank you."
Kyōraku laid a gentle hand on Shin's shoulder, offering a rare moment of genuine solemnity.
"Ukitake's not fully healed," Shin continued, "but his recovery has begun. He'll need time. He should remain here at the Fourth Division for now, under observation."
"Of course," Kaien nodded. "We'll leave it all to you."
Kotetsu Isane and Ise Nanao stared at Shin with awe. They'd known he was talented. But this?
They all entered the medical room together.
Ukitake lay on a reishi bed, pale but breathing. Unohana stood beside him, serene as ever.
No one spoke.
Until Kyōraku did.
"How's he doing?"
Whether he was asking Unohana or Ukitake himself, no one could tell.
Ukitake slowly opened his eyes, strained but smiling.
"Still alive," he said softly.
He felt it.
The weight in his lungs had changed.
It was heavier now—a paradox. All this time, he had not felt Mimihagi's presence. Only the stillness of the illness. Now, the pain was real. Tangible.
Has Mimihagi… left me?
Unohana's voice broke the silence.
"His condition is stable. Next step is adjusting the treatment plan. Isane, come with me."
The two left. Nanao followed a moment later.
Kaien turned to Ukitake.
"Taichō, just focus on getting better. Leave the division to me."
He followed them out.
Only Kyōraku remained.
He faced Shin, eyes solemn.
"Tachikawa Shin. What you did for Ukitake… for the Gotei Thirteen… for the Soul Society—it was a tremendous service. On a personal note, I will never forget it."
Shin didn't reply immediately.
He saw it coming—the next question.
Kyōraku's gaze sharpened.
"Ukitake's illness… being cured means that force has been removed. I didn't see the treatment myself—but I can guess."
"You saw it, didn't you?"
"Where is it now?"
He didn't say it.
But they both knew.
The Right Hand of the Soul King.
An existence with cosmic significance.
Shin wasn't surprised by the question.
He reached down, unhooked the plain-looking asauchi from his hip… and offered it.
"It's inside this blade."