"After all, I can't really let Yhwach destroy Seireitei."
"Brat, do you think I can't stop Yhwach?"
The current Yamamoto resembled a furious lion, his Reiatsu blazing like the scorching sun, seemingly about to incinerate everything around him.
Combined with Kyoya's earlier words, how could Yamamoto not understand what Kyoya meant?
"Captain-Commander, you've aged."
Kyoya's expression remained calm, his serene gaze unaffected by Yamamoto's Reiatsu.
But his words froze the air around Yamamoto like eternal ice.
"Whether you admit it or not, your physical strength has greatly declined."
"Even though your control over your power has improved considerably over this millennium, how many times can you unleash your full power with your current stamina?"
"And Yhwach is different."
"The resurrected Yhwach will only be stronger than he was a thousand years ago!"
"Moreover, since the Great Spirit Book Gallery records Yhwach's prophecy, it proves he indeed seized the world in nine days."
"Captain-Commander Yamamoto, you can't stop Yhwach."
"Rather than stubbornly causing greater losses to Seireitei, why not agree to my proposal?"
"I can guarantee you that against Yhwach's Quincy forces, the Revolutionary Army will stand with the Gotei 13."
"The Zanpakuto I need are hoped to produce at least a hundred officer-level or stronger members in the Revolutionary Army in twenty years."
"Then I'll lead Revolutionary Army's officers and above into Seireitei to resist alongside the Gotei 13."
"Additionally, Captain-Commander Yamamoto, if you don't mind, Yhwach can be left to me!"
"Hmph!"
"Brat, I'm not so old that I can't wield my sword!"
Dispersing the pressure around him, Yamamoto snorted coldly.
Though he had to admit that Kyoya's words made sense, Yamamoto wouldn't hand Yhwach over to Kyoya just because he said he'd die in the battle twenty years later.
He was the Gotei 13's Captain-Commander… blocking the enemy's strongest was his duty.
And...
Yamamoto looked deeply at Kyoya.
Currently, in the entire Gotei 13, besides himself, probably no one could withstand Yhwach.
So if only Kyoya were still in the Gotei 13…
But Yamamoto knew that if he forcibly kept Kyoya in the Gotei 13, someday the Seireitei's nobles would inevitably face Kyoya's purge.
Then, would he act against Kyoya?
If he acted, Yamamoto would struggle to convince himself whether he intentionally let Kyoya deal with the Seireitei's nobles to cleanse Seireitei.
If he didn't act, it would violate his 'court guard' duty. Whether Seireitei's future would become 'might makes right' rule, Yamamoto couldn't say.
Better to let Kyoya leave. Whatever Kyoya did in the future, any response he made would be clear-hearted.
However, the Gotei 13's strength was relatively weak.
In the battle a thousand years ago, though Yamamoto killed Yhwach, many surviving Quincy remained.
The original Gotei 13 was a group of killers that abandoned all 'justice' and 'mercy'… their combat ability far surpassed the brats of the current Gotei 13.
Moreover, the original Gotei 13's Captains all had at least 2nd-Class Reiryoku and completed Zanpakuto's Bankai.
Several had 1st-Class Reiryoku.
Among this generation's Captains, Unohana, Kyoraku, and Ukitake had first class Reiryoku.
Isshin might have broken through to 1st-Class Reiryoku within twenty years.
But unfortunately, a year ago Isshin went to the living world and lost his power.
Whether he could recover and return to fight remained unknown.
"I agree to your proposal!"
"Then Captain-Commander Yamamoto, pleasant cooperation!"
"Oh, Captain-Commander Yamamoto, I have another matter for coming to Seireitei this time..."
...
"Hmph, Kyoya, what do you take science for?"
In the 12th Division, Kurotsuchi shouted at Kyoya.
Honestly, if not for Yamamoto's request, Mayuri didn't want to see Kyoya again.
Truthfully, few people in this world could make Mayuri suffer.
Kisuke counted as one.
But after completing the Nemuri Project's seventh creation, Mayuri felt surpassing Kisuke was inevitable.
In Mayuri's view, Kisuke represented his past.
And Kyoya...
Well, up to now, Mayuri never forgot his arm being severed and heavily injured by Kyoya's sword.
After confirming Nemu's good condition, Mayuri devoted part of his energy to countering Kyoya.
Based on collected data of Kyoya's swordsmanship, Mayuri successfully modified his Zanpakuto into defensive means that could capture and completely block attacks within a certain range, plus attack modes that could launch aerial slashes.
But these alone couldn't match Kyoya.
Mayuri once collected Kyoya's Reiatsu and cells.
Initially, Mayuri could learn about Kyoya from these.
But later, Mayuri suddenly discovered terrifying changes in the collected Reiatsu and cells.
He could no longer obtain any information about Kyoya from them.
Then Mayuri knew Kyoya's level exceeded his imagination.
But simultaneously, Mayuri felt that if he could decipher these changes in Kyoya's Reiatsu and cells, he would definitely discover something.
Something perhaps higher than his [Nemuri Project's] essence.
But looking at Nemu, whom he raised, Mayuri couldn't speak words abandoning the Nemuri Project.
Nemu was Nemuri No.7.
In Mayuri's view, his project wasn't fully mature.
Thus, Nemu's body and soul had many defects.
These defects might affect Nemu's lifespan.
Over the years, Nemu's survival and gradual growth required Mayuri's energy invested in the Nemuri Project.
Through repeated experiments, he slowly repaired Nemu's defects, making her gradually approach 'completeness'.
Before completely solving Nemu's lifespan defect, Mayuri didn't want distractions researching other things.
Thus, Nemu long transcended 'test subject' category for Mayuri.
Calling her his daughter wasn't excessive.
But Mayuri abandoning Kyoya research didn't mean he wanted to see Kyoya.
Who would have thought Kyoya directly approached Yamamoto, saying he wanted to conduct research in the 12th Division, requesting Mayuri's cooperation.
Hence Mayuri's anger.
What did Kyoya think science was?
'Did this brute understand science?'
In Mayuri's impression, Kyoya belonged with Zaraki as 'brutes'!
Yamamoto asking him to guide Kyoya's research… what was this?
Punishment?
"Don't be so angry, Captain Kurotsuchi."
Kyoya smiled and waved at Mayuri: "I come with sincerity."
"Sincerity?"
Mayuri looked Kyoya up and down in surprise: "Hoho, what sincerity?"
"Captain Kurotsuchi, my sincerity naturally is-"
"I believe you're the scientist with the deepest Zanpakuto research, hence asking the Captain-Commander to designate you to teach me how to draw power from my soul to create Zanpakuto."
"With your control over the 12th Division, you probably know I visited the living world recently."
"There, I met former 12th Division's Captain, Urahara Kisuke."
"But after comparison, I felt you're more reliable."
"Otherwise, I wouldn't be here but directly asking Urahara Kisuke in the living world."
"Hmph!"
"Seems you have some discernment."
Hearing Kyoya's words, Mayuri snorted.
Contrarily, his expression relaxed, corners of his mouth slightly upturned.
Indeed, Kyoya understood Mayuri deeply.
Saying Kisuke couldn't match Mayuri directly scratched his itch.
Though Kyoya's words wouldn't make Mayuri forget the humiliation from Kyoya, to prove Kyoya's discernment correct, Mayuri would indeed spare no effort teaching Kyoya Zanpakuto Modification.
"Follow me!"
"Alright, sorry for the trouble, Captain Kurotsuchi!"
Following Mayuri, Kyoya felt nothing improper.
He came to learn from Mayuri, naturally hoping for his full effort.
At such times, he wouldn't oppose Mayuri.
The One Piece Achievement System bound to Kyoya's soul.
Its achievement rewards naturally resided within his soul.
When Kyoya used achievement rewards, they became soul light points merging with his soul, strengthening him.
But achievement reward items had great randomness.
Like Devil Fruits.
Kyoya's first Devil Fruit was the Logia, Pika Pika no Mi, which was already used as his Zanpakuto in this world.
But both One Piece and Bleach Worlds had ability 'uniqueness'.
In One Piece World, one could eat only one Devil Fruit, and eating more meant death.
In Bleach World, Shinigami had only one Zanpakuto.
Of course, both worlds had rule-transcending individuals.
In One Piece World, Marshall D. Teach, the son of legendary pirate Rocks, had abnormal physique allowing two Devil Fruits and abilities.
In Bleach World, the God of Sword, Nimaiya Oetsu, creator of Asauchi, possessed multiple Zanpakuto.
Unless Kyoya obtained Teach's physique enabling second Devil Fruit and Zanpakuto-
Otherwise, these Devil Fruits in his soul were decorations.
Among these Devil Fruits, some matched or surpassed the Pika Pika no Mi, but Kyoya had developed light abilities to their limit, fully integrating all his abilities through light.
Thus, he couldn't replace the Pika Pika no Mi.
Rather than letting these Devil Fruits lie idle in his soul, Kyoya wanted to separate them, forge them into Zanpakuto for Revolutionary Army use.
Presumably, with these Devil Fruit Zanpakuto, some Revolutionary Army's cadres, Vice-Commanders, or even Commanders could greatly improve.
Indeed, actually interacting, Mayuri was quite agreeable.
Especially with Kyoya knowing Mayuri was 'tsundere', targeted praise greatly increased Mayuri's favor.
And all this was seen by one person.
...
After leaving the laboratory, Kyoya locked the door and headed to his residence.
Not that he returned to Rukongai, but during his studies with 12th Division, Mayuri arranged accommodation.
But...
Corners of his mouth slightly upturned, Kyoya didn't return but went to a courtyard.
The bright moon cast ripples in the pond.
Breeze gentle, willows graceful.
"The moonlight is beautiful tonight, don't you think, Lieutenant Nemu?"
"When did you discover me?"
Following Kyoya's voice, a shadow emerged from behind a corridor pillar.
Under moonlight, Nemu's expression differed greatly from her usual 'expressionless'.
"Lieutenant Nemu, when did you think your stealth could fool me?"
"After all, I was Captain of the Gotei 13's 11th Division."
"Did you overestimate your ability, or do you misunderstand Captain-level strength?"
Kyoya turned, smiling as he questioned Nemu.
"Is that so?"
Nemu tilted her head, eyes showing confusion.
"But I've followed Fathe-"
"I've followed Captain so many years, he never noticed..."
"Well..."
"I think two possibilities."