The Cistern Is Full, Yet It Does Not Overflow

The cistern contains: it does not overflow.

--William Blake, The Marriage of Heaven and Hell (1790-1793)

Muramasa walked alone along the pipeline corridor deep inside the research institute. Cables hanging from the ceiling and Reishi tubes extending along the walls swept past him on both sides. His footsteps were so light that they made almost no sound on the metal floor.

The structure here is completely different from other Soul Reaper buildings—the walls are covered with constantly flashing indicator lights, a wisp of extremely thin white steam occasionally emanates from the joints of the pipes, and the air is filled with the pungent smell of high-concentration Reishi disinfectant.

Muramasa finally stopped in front of the tightly closed metal door at the deepest part of the passage. He raised his right hand, his long-fingered hand resting on the door.

"A chilling and cruel Reiatsu, like that emanating from the abyss—there's no doubt, he must be here."

He cleaved open the door with his knife and stepped into the thick darkness. The passage was extremely narrow, allowing only one person to pass at a time. Every few steps, a dim emergency light was embedded in the wall. He walked until he reached the middle of the passage—

Suddenly something fell in front of them, the sound extremely deep, like the foot of a giant beast stepping on a stone slab.

It was a metal box as tall as a person, covered with dark silver alloy armor, with thick bolts riveted to its edges, firmly blocking the way.

At the same time, a similar muffled thud came from behind, and their retreat was also blocked.

The two metal boxes emitted the characteristic snoring sound of depressurization simultaneously, white steam gushing out from the seams. The boxes facing Muramasa slowly tipped over, crashing heavily onto the metal grille, revealing their contents:

Those were two exquisitely crafted life-size Reishi Dolls.

The figure in front was burly, covered in heavy armor, with broad shoulder armor like two shields, and the visor on the helmet emitted a faint red light.

With its left hand, it held a massive tower shield, the width and height of which could perfectly fill the entire passageway, while with its right hand, it gripped a long spear, the tip of which protruded from an opening in the shield and was aimed at Muramasa's chest.

The one behind Muramasa was even more bizarre—in addition to its own two arms, it had two extra pairs of flesh and blood arms attached to it, and it was holding two bows made of pure Reishi. The bowstrings were stretched to their limit, Reishi arrows had already condensed on the strings.

"A pincer attack? Setting up two Reishi Doll like this in a passage where even turning around is difficult, most intruders would probably die here."

Muramasa Zanpakuto horizontally in front of him, and before he could finish speaking, the heavily armored Reishi Doll in front of him had already moved.

The heavily armored Reishi Doll pushed its shield forward, the tip of its spear bursting with incredible speed over a very short distance, aiming straight for his throat.

At the same time, a rain of Reishi arrows tore through the air behind him, targeting his back.

"Unfortunately... it's useless against me!"

The next instant, the heavily armed Reishi Doll flew out from the other side of the passage. The Reishi Doll's hands and feet were still twitching, its fingers were unconsciously bending and straightening, and the gears at its joints were making a clicking sound.

Muramasa dragged the multi-armed Reishi Doll out of the passage. The Reishi Doll was still resisting, but Muramasa was in a daze, crushed its head with a single blow.

At this moment, Muramasa's gaze was drawn to the transparent storage jar in front of him.

The container almost reached the ceiling, filled with a pale blue liquid. Floating in the liquid was a Zanpakuto —a white hilt with a pair of hexagonal tsuba, its blade long and simple, gleaming with a cold light.

"Jiku'a"

When Muramasa the name, his voice trembled with an extremely rare quality.

There was no mistaking this aura—cold, sharp, and pure to the point of being domineering. He took a step forward, his gaze fixed on the storage jar. "Kōga is finally saved..."

Until something blurred in his vision. A drop of dark red liquid fell onto the metal grille. He raised his hand to touch his eye socket, his fingertips stained crimson—blood.

"Sooner than expected." He wiped the blood from the edge of his eye socket with the back of his hand. "We need to wake Jiku'a quickly."

Muramasa walked toward the storage tank, stepping over the still-sizzling data cables on the floor and onto the platform radiating white light surrounding the tank.

Almost the instant his feet stepped onto the glowing platform, his body was suddenly slammed to the ground by a tremendous force. His chest pressed against the cold metal surface, his fingers dug into the seams of the floor, and his nails scraped against the metal surface with a harsh, grating sound.

"Hmph hmph hmph..."

Laughter came from the shadows to the side, Mayuri Kurotsuchi stepped out, his face etched with undisguised mockery.

"As expected, Zanpakuto is Zanpakuto; its thoughts and actions are so simple."

He walked over to Muramasa, looked down at the Muramasa who was immobilized by the magnetic field, tilted his head, revealing a mouthful of teeth that appeared particularly yellow in the shadows, and said, "You don't actually think my lab is only guarded by those two dolls, do you?"

"Captain of the Twelfth Division, Mayuri Kurotsuchi?" Muramasa barely managed to lift his head, his neck cracking from the pressure. "Is it really a good idea for you to abandon those soldiers and leave the battle like this? None of those Soul Reaper can even use Shikai. Aren't you afraid they'll be slaughtered by my comrades?"

At this moment, Nemu's side

She stood in front of the cylindrical container, arms outstretched, leading the vanguard. Beside her were a dozen or so members of the Twelfth Division, their Shihakusho stained with dust and blood, their defenses being pressed closer and closer.

A Zanpakuto wielding a massive, Zanpakuto cleaved a member of the squad, sending him and his sword flying. The member crashed into the wall and slid down its Shihakusho, a deep gash ripped into his chest. The Zanpakuto the sword back over his shoulder and spat, "Apart from that woman, the rest of them are so weak. Are they really Soul Reaper?"

Beside him, a Zanpakuto squatted on the ground, holding a severed head in his hand, toying with it. "The Twelfth Division truly lives up to its reputation as the division with the lowest Shikai among the Gotei 13; their combat strength is incredibly weak."

Meanwhile, Mayuri Kurotsuchi...

Instead, he grinned, a smile with an inexplicable eeriness, "Hehehe, don't underestimate my Researchers, those guys are no pushovers..."

Exterior room

The slender, bamboo-like Zanpakuto held the head up to its face, and a strange smile hung on the head's face, the corners of its mouth stretching almost to its ears.

Looking into those unseeing, lifeless eyes and that eerie smile, a strange irritation welled up inside him. He slammed his head to the ground. "Laughing even in death, disgusting!"

He kicked the head away, but what he didn't know was that the head was turning into a viscous, almost liquid substance.

The headless corpse of the Soul Reaper began to melt, the fabric of his Shihakusho collapsed, and the flesh and bones inside slowly deformed like a block of wax thrown into hot water. Two clumps of viscous matter secretly gathered together in the darkness, silently reshaping behind the Zanpakuto, first the outline of the bones, then the texture of the muscles.

The Soul Reaper stood in the shadows, looking at his hands, and moved his fingers, which had just reformed, making a very slight clicking sound from each joint.

He raised his head, looking at the group of Zanpakuto still fighting his comrades in front of him, his eyes growing brighter and brighter:

"Success! I've finally replicated the captain's fluidization modification. No, it's not time to celebrate yet— the Zanpakuto's transformation, a new challenge, new possibilities, hehehe..."

He dragged his still-healing legs, inching his way toward the wall, leaving a wet trail behind him.

The skinny, bamboo -Zanpakuto, after kicking open a skull, turned back to continue fighting the members of the Twelfth Division. But for some reason, he sensed something moving behind him. He instinctively glanced back, and his pupils suddenly contracted.

--The Soul Reaper who should have died has miraculously come back to life. He is dragging a leg that is still dripping liquid tissue, moving step by step toward the wall. There is a switch in the direction he is heading.

"Hey, what do you think you're doing!" The skinny bamboo- Zanpakuto turned around, gripping the blade as it charged towards the slowly moving figure.

But the Grim Soul Reaper didn't take him seriously at all, and simply reached out and pressed a button on the wall, causing the entire building to shake.

New walls slowly slid out from the gaps in the torn ceilings, sealing the openings piece by piece.

The windows were covered with partitions, the door frames were blocked by armor plates that rose from the inside, and the white light of the Reishi lamps began to flicker. After everything stabilized again, all the doors, all the windows, and all the ventilation ducts were locked.

The skinny, bamboo -Zanpakuto grabbed the Soul Reaper by the neck, lifting him off the ground, his voice filled with rage. "What did you just do!"

The Grim Soul Reaper was suspended in mid-air, his neck being choked so hard he could barely breathe, but there was no fear in his eyes.

He reached out, his fingers gently resting on the hand that the slender bamboo- Zanpakuto, as if appreciating a precious work of art, his fingers slowly tracing the Reishi patterns on the skin.

"So the materialization of Zanpakuto's will is different from when Soul Reaper spontaneously materializes it... This body is almost like Spirit Body... This phenomenon is truly fascinating."

He tilted his head and licked his lips. "We didn't capture enough Zanpakuto yesterday, and the captain wouldn't let us touch them. Hehe, we caught so many today, surely we should get a few now."

Ah~ I really want to dissect you and see what's inside.

That expression Zanpakuto a chill down the spine of the skinny Zanpakuto.

He slammed the Soul Reaper to the ground, stomped on his chest, and swung his sword down. Perhaps because it hadn't fully solidified yet, the sword strike caused the Soul Reaper's body to become like a viscous liquid, only causing ripples on Soul Reaper surface.

Meanwhile, on the other side, the Zanpakuto wielding the giant Zanpakuto was slashing at the newly appeared metal wall. The blade struck the wall, sending up blinding sparks, but the wall remained completely still.

"Something's wrong with this thing, I can't open it at all!"

The Soul Reaper, pinned to the ground, turned his head and looked at the Zanpakuto struggling against the wall, a dazzling smile spreading across his lips:

"Of course it can't be opened. This is a protective measure to prevent the spread of harmful results from the laboratory. It uses materials containing Sekkiseki, so it can't be easily destroyed."

He laughed heartily, as if he were seeing endless experimental data and the experimental subjects beckoning to him.

At that moment, the Soul Reaper who had Zanpakuto down by the Zanpakuto began to stand up one by one.

Some wounds were crawling with strange worms, and the wounds that the worms crawled over all stuck together. Some had a huge hole pierced through their chests, and their hearts were nowhere to be found, but they got up and inserted a mechanical heart into themselves.

Their methods of treating themselves were bizarre and varied, but their eyes burned with the same fervor—the kind of fervor that erupts after countless days and nights spent in the laboratory finally obtaining the long-awaited sample.

The skinny, bamboo -Zanpakuto involuntarily took a step back. "What's wrong with these guys...?"

Deep within the research institute, Mayuri Kurotsuchi stood before the Muramasa, its surface suppressed by the magnetic field, continuing his swagger, "The members of the Twelfth Division may not be good at field operations, but coincidentally, you bunch of idiots have trespassed onto our territory."

He looked down at Muramasa, "We happen to have a lot of research results and are just worried about not having any experimental subjects."

Muramasa lay prone on the ground, his face expressionless, which puzzled Mayuri Kurotsuchi. He had seen many people who valued their comrades react when they heard that their comrades might be attacked, but Muramasa's behavior was clearly not one of them.

"Oh dear, you keep calling people 'comrades' and 'comrades' all the time, but now you don't even seem nervous at all. It seems you're not as righteous as you claim."

Muramasa didn't say much about it, but silently tried to figure out how to break free from the suppression of the magnetic field.

Mayuri Kurotsuchi crouched down, his voice carrying an absolute, researcher's arrogance. "Come on, tell me, how did you manage to materialize the will of your Zanpakuto? Why is it opposed to its wielder? Is this your ability as Zanpakuto?"

Muramasa looked up at the man, at the inextinguishable, greedy flame in his eyes for the unknown.

"There's nothing to say to someone like you whose emotions are filled with the desire to study, and who doesn't even have a shred of Zanpakuto," Muramasa said disdainfully.

"So, the Kōga you're talking about, is it the one with Zanpakuto in his eyes?" Mayuri Kurotsuchi narrowed his eyes slightly, his lips curling into an even more exaggerated, mocking smile.

When Kōga Mayuri Kurotsuchi uttered the words "Kyouga," Muramasa surprised, a fact that Mayuri Kurotsuchi noticed.

"Who is he?" Mayuri Kurotsuchi tilted her head. "Could he be your master?"

Mayuri Kurotsuchi took a step forward and looked at Muramasa: "What do you mean 'he's saved'? Why Jiku'a able to save him?"

Muramasa realized that Mayuri Kurotsuchi had deduced some truths from his reaction, and he couldn't help but feel some pressure, which manifested in the bloody tears that began to flow uncontrollably from his eyes again.

"Blood? I've been wondering about this. Is this blood? Zanpakuto aren't living beings and shouldn't bleed. But you're strange; the Zanpakuto you've influenced have all gained Spirit Body. This made me think for a moment that the Zanpakuto had become independent entities. How did you do that? Where did you get these Spirit Body from? Tell me quickly!"