"Nine thousand eight hundred sixty-seven… nine thousand nine hundred ninety-nine!"
"Not bad at all, brat."
In the sealed chamber, Shutara Senjumaru's lazy voice echoed. Her half-lidded eyes flashed with a hint of surprise.
"I didn't think you'd actually stick it out. Just in terms of willpower, I'd gladly call you the strongest."
In the center of the room, Naraku Sora stood bare from the waist up, his muscles cut almost to perfection. His shoulder blades bulged with coiled strength, his spine taut like a fully drawn bowstring.
He stood before a pure white wall, as if drenched in a sudden downpour, streaks of moisture marking the surface all around.
With a low, heavy shout, Naraku's right fist drove forward.
Boom!!!
At the moment fist met wall, a dull shock burst outward. A visible shockwave rippled from the point of impact, spreading violently in every direction.
After landing the final punch of his training, Naraku slowly exhaled a lungful of stale air. A sharp light flickered in his eyes.
"I really did make it…"
Even he hadn't expected to actually get through a regimen that was basically hell.
This was the spirit-body tempering chamber Shutara had built years ago, designed specifically for training the spirit body.
Anyone inside was constantly subjected to crushing Reiatsu pressure—and as the user's tolerance rose, the chamber automatically increased the pressure to match their new limit.
When someone with weak Reiatsu faced a truly powerful existence, the gap alone could completely rob them of the ability to fight. Some might faint on the spot. Some might die.
Even Coyote Starrk mentions this kind of thing in his autobiography.
If it was just Reiatsu pressure, the tempering chamber wouldn't have been worth Shutara's personal effort.
Besides the external pressure, the reishi inside the space was abnormally active, immediately repairing any micro-damage to the spirit body as it appeared.
Not only did that ease the negative impact of the Reiatsu and help the user quickly adapt to a high-pressure environment, letting them train far longer—
It also toughened the spirit body itself through repeated damage and repair, boosting its resilience and durability.
All those benefits came with a catch, of course.
The process hurt like hell—far beyond what normal Shinigami could endure.
Just lasting a few minutes was already the limit for most.
Even so, people kept coming to try.
For one simple reason: this kind of training really made you stronger.
In Naraku's case, his spirit body had already been enhanced, and with his growth potential doubled, his entire being had undergone a gorgeous transformation from head to toe.
Under those conditions, this chamber might as well have been custom-built for him.
As long as his iron will held, he could keep training right up until his mind completely burned out.
No fancy techniques required—just put everything into every single punch.
Naraku felt like a block of steel, being forged and reforged, changing bit by bit with every strike.
Keep going.
After a brief adjustment, Naraku focused on the white wall in front of him again. The wind from his fist shrieked out, driving straight into it.
Boom!
The thunder of impact rang out over and over, like a rousing symphony pounding toward its true climax.
Crushing pressure surged in from all sides, as if he were at the bottom of the sea. Even his internal organs felt like they were nearing their limit.
This was full-spectrum training for the spirit body.
As the pace picked up, the ferocity deep in Naraku's bones began to surface. His grin turned steadily more savage, the same look he wore in real combat.
His eyes were bloodshot, his lips pulled back in a near-feral arc. The wildness of it all made Shutara sigh in a strange sort of admiration.
"This look really does remind me of someone."
"That guy used to fight exactly like you when he was younger. Even now that he's calmed down a bit with rank, he still hasn't shaken that 'advance like wildfire' style."
Thinking of this, a thoughtful glint passed through Shutara's eyes.
"Maybe I should find this brat a teacher…"
While she pondered, Naraku's training burned even hotter. Every inch of his body became a weapon, every blow crashing into the unyielding wall.
His skin split open under the backlash, lines of cracks appearing as blood mixed with sweat, seeping out—only to be rapidly repaired by his powerful regeneration.
Over and over, like a perpetual motion machine.
Shutara noticed something.
"Hm. If I'm remembering right, the tempering chamber's reishi field alone shouldn't be able to repair you that fast."
"Is that your spirit body's own regeneration?"
"Or… is it the Hollow power?"
As her words drifted off, her slender fingers began to tap the air. Countless threads of reishi appeared out of nowhere—
Weaving, twisting, wrapping.
Shutara used them to measure Naraku's training data:
Peak Reiatsu output, state of the spirit body, rate of mental fatigue… and so on.
Whenever Naraku brushed against the reishi threads, he wasn't disturbed in the slightest.
One of them was lost in the thrill of training; the other, engrossed in data.
They were in sync in a way that felt… oddly unsettling.
At first, when Naraku learned that Shutara knew about his Hollow Power, he'd panicked a little. But as they spent more time together, he realized this "bad woman" wasn't the same species as normal Shinigami at all.
Or maybe, every high-end researcher in Soul Society had at least a few screws loose.
So now, when it was just the two of them, he'd simply given up pretending. He barely cared about "secrets" anymore.
They were both equally weird anyway.
Boom!
On his final strike, a red light flashed in Naraku's eyes. His fist, wrapped in blood-colored Reiatsu, slammed into the wall.
In an instant, the shockwave tore through the sealed chamber, shredding all the reishi threads around him.
"Well, looks like we're finally done."
Shutara lifted her head, her mature, refined profile catching the light as her lips curved upward.
"Your performance honestly exceeded my expectations."
...
...
Leaving the tempering chamber, Naraku dragged his exhausted body toward his quarters.
As the Central Prison's Tenth Seat Jailer, he not only had a room in the barracks but had even been assigned his own longhouse estate.
He just almost never stayed there.
But the moment he slid open his door, a cold gleam of steel shot straight at him. The attack was so fierce it split the air with a deafening crack.
Naraku's eyes sharpened. Crimson Reiatsu exploded from him.
At such close range, there was no time to draw his sword.
His body moved on instinct—his fist wrapped in Reiatsu and drove forward.
Boom—
Their fists collided, and a visible shockwave burst out in an instant. The floor beneath their feet splintered into a spiderweb of cracks.
A gift from the Araki family—
The assassins had arrived!