As for what happened after, Yoshio could guess easily.
After learning the truth of this world, Hinamori's worldview collapsed.
She began to feel that Shinigami were no longer her comrades, but her enemies.
Even Yoshio's image in her heart darkened quite a bit at that moment.
After all, Aizen didn't pull Yoshio into their two-person cell—if you're going to oppose all Shinigami, then it's only natural her favorability toward Yoshio would drop.
Still, Hinamori wasn't that extreme; she still had over 80 favorability toward him.
Makes sense. To put it bluntly, what a group is like… doesn't necessarily have that much to do with every individual in it.
Maybe, deep down, Hinamori still hopes Aizen would recruit him as a companion.
But…
Forget it.
Yoshio wasn't interested in Aizen's newly formed group. If anything, he really couldn't bring himself to deceive Momo.
After spending so long together, Yoshio wasn't dense. He could watch Hinamori Momo get played by Aizen, but he wasn't about to take part himself.
Sigh.
This villain Aizen really ought to be taken out.
Yoshio shook his head and said, "Captain Aizen, you're really bad."
Aizen smiled, unfazed by Yoshio's impudence. He only said, "I merely told Hinamori what the Shinigami have done. As for how she chooses, that's her own will."
"True. The Shinigami have done too many shameful things. If all that unpublishable history got made public, no wonder hearts would waver," Yoshio said, putting on a nonchalant air.
In truth, whatever Hinamori chose, Yoshio would support her.
Like Aizen said, Shinigami aren't some lily-white race. Just because they fought alongside Kurosaki Ichigo, did you really think they were good people?
Not everyone on the protagonist's side is a good guy—they could be Orochimaru; they could be Aizen Sosuke.
Aizen helped the protagonist fight the final boss. You can't say that makes Aizen a good person.
So Yoshio simply set aside Hinamori's matter and said, "By the way, Captain Aizen, take a look at this Hogyoku."
He took out the Hogyoku he'd refined yesterday and handed it to Aizen.
Aizen was a bit surprised. "You've already made one this quickly?"
He took the Hogyoku and examined it.
"I was only missing a Quincy soul to begin with, which is why I orchestrated that earlier incident," Yoshio said. "Once it wrapped up, I immediately started phase two. Also, thanks to the materials you provided, Captain Aizen."
"But during the experiments, I found the requirements for Quincy-ization were too high. Even Arrancar souls weren't strong enough."
Aizen studied the Hogyoku, thoughtful.
After Yoshio finished, he said, "So, you want me to help you test it?"
"That's the idea." Yoshio scratched his cheek, a little embarrassed. "I'm not the best at research. See if there's anything you can improve, Captain Aizen."
"…Come find me next month," Aizen said, pocketing the Hogyoku without ceremony. "I'll perform some adjustments this month."
See?
A good advisor is invaluable!
Not only no defense required, he'll even help perfect your thesis.
I'm—moved to tears.
Feeling grateful, Yoshio bought two bottles of sake on the way back.
…
When he returned to Division 10, Rangiku saw the bag and got a black line on her forehead. "You managed to hold out just one day before dropping the act?"
"You don't get it," Yoshio said. "I only work better when I'm drinking."
He set the bottles in the office, then came out again. "Oh right, I heard Central 46 has decided on Captain Shiba's disposition?"
"…It's serious," Rangiku said after a brief silence.
"Not only is Captain Shiba treated as a traitor, but the Shiba clan is implicated. I hear Central 46 and the Golden Seal Noble Council may expel the Shiba from the Five Great Noble Houses."
Yoshio sighed.
"The Shiba are truly ill-fated," he said wistfully. "First, a rare genius, Shiba Kaien, died; now another captain, Shiba Isshin, goes missing…"
"But you're not a noble, so you don't understand their political ecosystem. Being expelled from the Five Houses might actually be good for the Shiba who remain."
"Good?" Rangiku was confused.
"The Shiba may be one of the Five, but have you heard of any real influence? They're more like a mascot. They've been ostracized for years by the other four, especially the Tsunayashiro."
"Though the Tsunayashiro have declined abnormally now, many still fear them."
"So losing the Five Houses title isn't so bad for the Shiba. At least they'll avoid Central Seireitei's treacherous political vortex."
"Maybe…" was all Rangiku could say.
She was just a lieutenant; there wasn't much she could change.
…
A month later, two major events shook Seireitei.
First: the Shiba were expelled from the Five Houses. They chose to leave Seireitei and go to the Rukongai.
Second: Division 13 Captain Ukitake Jushiro chose to retire, passing the captaincy to his lieutenant, Hitsugaya Toshiro.
Those with ability in Seireitei had predicted both long ago, so they didn't spark huge debate—just rank-and-file Shinigami arguing red-faced.
Ukitake should've stepped down long ago, but after the Substitute Shinigami incident, he stayed out of responsibility.
Later, he was ambushed during the Wraith incident and realized he truly might be old, and it was time to pass the torch.
There was also a small matter in that second event:
When Hitsugaya Toshiro became captain of Division 13, Kuchiki Rukia, the Kuchiki heiress, became the squad's lieutenant.
Rukia hadn't even been a seated officer, yet leapt to lieutenant—a surprise to many.
But they all knew Rukia had the strength. The only reason she hadn't been promoted before was that Kuchiki Byakuya had secretly signaled Ukitake not to seat her.
The higher the position, the more the danger.
Byakuya didn't want Rukia exposed to danger.
But now Rukia was strong enough; suppressing her further would be pointless and might arouse suspicion. So Byakuya didn't tell Hitsugaya anything.
After being promoted, Hitsugaya immediately had Rukia take his former position.
When Yoshio arrived at Division 13, Toshiro was diligently handling paperwork.
Seeing him work so earnestly, Yoshio was reminded of his own days in Division 5 and couldn't help but sigh.
Toshiro frowned. "You look awfully relaxed for a captain. Don't tell me you're dumping all your work on Matsumoto."
"You punk…" Yoshio shook his head helplessly. "Where do you get so much work every day? You're just making yourself look hardworking."
"If you improve efficiency, a captain's workload isn't much. You're still too young.
"Hurry it up. After you finish, we settle our business, and then you're coming to my place for dinner tonight."
"Captain Kyoraku, Captain Ukitake, and Captain Aizen will all be there," Yoshio said.
"Huh?"
Rukia's voice came from the door. She looked at Yoshio. "Is there some kind of captains' gathering today?"
"Ah, congrats on becoming a lieutenant, Rukia," Yoshio said first. "It's not really a gathering—more like a meal together since Captain Ukitake has stepped down."
"I see… Then…" Rukia glanced at Toshiro. "Captain Hitsugaya, why don't I handle this paperwork?"
"I'm so touched," Yoshio cut in before Toshiro could speak, sighing. "If Rangiku had this sense of responsibility, I'd die of happiness."
Rukia blushed. "It's just that Captain Hitsugaya has helped me a lot, so…"
"No need. I'm finished here."
Setting down the last document, Toshiro stood.
"Let's go, Yoshio-san."
"Hey, Captain… what are you going to do?" Rukia asked. Yoshio had said they'd settle their matter first, then eat. So… what matter?
"This brat wants to fight me."
Yoshio shrugged. "Looks like this kid needs a beating and wants to turn the heavens upside down."
Rukia stared at Toshiro. He said, "Don't overthink it. I already applied to the Captain-Commander. We're just not allowed to fight in Seireitei. If we move to Rukongai, it's fine."
…
Thus, Yoshio and Hitsugaya appeared in Rukongai.
Of course, they wouldn't fight in a populated district—that'd ruin it.
Beyond the townships are vast stretches of emptiness—mountains, wilderness, grasslands…
No one lives there: the perfect battleground.
Back then, Shiba Isshin and Zaraki Kenpachi fought in a similar area.
Captains cannot fight in Seireitei; it sets a bad example.
If a captain loses, wouldn't his subordinates feel inferior to the other squad?
"Shiro, don't say I'm bullying you."
They stood in a wasteland. It was afternoon, yet the area was strangely dim.
Sunlight seemed unable to penetrate thick clouds; what reached the ground was only a dim afterglow.
On the cold earth, Yoshio faced Hitsugaya and said, "I'll let you open your bankai first. Otherwise, you might not even get the chance to attack me with it."
It sounded condescending, but Toshiro didn't get angry. He knew from the start that Yoshio was no ordinary Shinigami.
He believed Yoshio's talent might surpass his; a Shinigami possibly more gifted and with years more training—of course he deserved Toshiro's full strength.
"Then be careful," Toshiro said solemnly. "I still can't fully control Daiguren Hyorinmaru's power!"
"Bankai—Daiguren Hyorinmaru!"
!
Boom!
In an instant, vast reiatsu erupted from Toshiro's body. The surge thickened the ambient moisture on contact; the air grew even colder.
It was summer, yet snow began to fall thanks to Daiguren Hyorinmaru.
"Heaven manifests," Yoshio murmured, surveying the space. "Enviable—such a dramatic field, built-in."
"You won't even release your Zanpakuto?" Toshiro frowned. "Even if you look down on me, there's a limit."
He'd used bankai, but Yoshio hadn't even released.
"You should know," Yoshio said, "my Zanpakuto isn't for sparring. It either does nothing, or it sends people to hell."
"At least for now, we're just sparring."
Softly, he added, "So I won't use my Zanpakuto's ability."
"But don't worry about fairness. My bankai is special. Even without releasing, I can use part of its power."
Toshiro's pupils tightened as Yoshio extended his hand—and a massive fireball formed in his palm.
Fireball!
Boom!
The roaring flames crackled with unstable explosive reiatsu.
This was one of Yoshio's soul abilities—the fireball—but he disguised it as bankai output.
He hadn't disclosed much about his bankai, only submitted written documentation to Captain-Commander Yamamoto.
In the Gotei 13, only he and Aizen likely knew his true ability.
Not unusual—hiding a Zanpakuto's powers is standard, especially bankai—every Shinigami's biggest trump card.
Meaning, Yoshio could attribute all his soul abilities to bankai.
As the fireball swelled, the snow around them melted.
"Ryusenka!"
Seeing Yoshio wasn't bluffing, Toshiro attacked.
The vast icy wings at his back beat as he thrust toward Yoshio.
Yoshio hurled the fireball, and in the same instant pointed a finger at Toshiro.
"Chain Lightning!"
Crack!
As the fireball flew, a bolt of lightning lanced out, then braided into the fireball—light and heat erupted, lightning skittering over the sphere's skin, doubling its power!
?!
Toshiro's eyes widened. He swung—ice engulfed the fireball, only to melt on contact.
He could only force a course change and evade as best he could.
Boom!
He narrowly dodged; the huge fireball detonated in the distance.
The explosion rolled back, the blast and heat striking Toshiro's back, shunting him forward several meters, shuddering his reishi.
"Stunning Blow!"
At the same time, Yoshio appeared before him. His unreleased Zanpakuto seemed to gather a hidden glow as he cleaved down!
Stunning Blow was a seat officer from Division 4's soul ability: attacks inflict stun and may outright knock the target unconscious.
Yoshio rarely used it; he usually relied on Ceros or Hell powers. Now, he'd try it on Toshiro as a test.
Toshiro blocked, but his strength was no match. Yoshio slammed him from sky to earth.
His head swam; he nearly blacked out.
Is the gap really this big?
Looking up at Yoshio, Toshiro was shaken.
He believed he deserved a captaincy even if it had been ceded by Ukitake. He didn't expect to be suppressed by a near-contemporary captain.
As Yoshio lunged again, Toshiro raised his blade and murmured, "Sennen Hyōrō!"
Moisture around Yoshio froze at once; towering walls formed in a blink to seal him in.
"Your ice is not my equal to fire."
From within, Yoshio said, "I tested this already—you didn't notice?"
Boom!
Another fireball shattered the ice. He looked down at Toshiro but didn't pursue. "You think controlling ice is your exclusive domain?"
"Blizzard."
He spoke softly; then countless pillars of snow hammered down from the heavens!
Those snow pillars were in no way inferior to Hitsugaya's ice pillars, now crashing down everywhere!
"How is that possible?!"
Toshiro stared. "How did you…?"
He wasn't shocked that Yoshio could command storm and snow within Hyorinmaru's field—he was stunned by how Yoshio wielded so many powers at once.
Fire, lightning, now wind and snow?!
Impossible!
A Zanpakuto cannot command so many abilities simultaneously!
"Who knows," Yoshio said. "Maybe they asked me to command them."
Toshiro had no time to speak—he fled, stepping through the storm.
A prodigy, his shunpo was high level. He danced between the strikes—only to feel a jolt of danger.
Yoshio had arrived there first.
As Toshiro flashed in, Yoshio's hand was already raised. He placed a finger to Toshiro's chest—almost as if Toshiro had stepped into it.
"Hado #4: Byakurai."
He spoke quietly.
Schlick!!!
A bright bolt flashed from Yoshio's fingertip!
It pierced Toshiro's chest with ease and lanced far into the distance!
Toshiro's eyes widened, dazed. He looked at Yoshio, gritted his teeth, but said nothing.
"I… lost."
Yoshio's control was precise. Though Byakurai pierced Toshiro's chest, it missed vital points.
"Don't belittle yourself," Yoshio said gently. "Hyorinmaru is the strongest ice/snow Zanpakuto. Its true power is far beyond this."
"The future is yours."
"No. Losing is losing. Talking about the future sounds like I can't accept defeat." The ice wings vanished.
He'd thought he might lose, but not so quickly—especially when Yoshio hadn't even released.
"This isn't sour grapes; it's objective fact," Yoshio said. "Hyorinmaru condenses ice from atmospheric moisture. The longer you fight, the stronger it gets."
"Some can beat you early—even one-shot you. But if the battle drags on, you may surpass them."
He wasn't making it up—Hyorinmaru is like that.
In incomplete bankai, early Hyorinmaru isn't much above shikai.
Obvious example: against Harribel, pre-Resurrección Harribel overpowered bankai Toshiro easily. After she released, her pressure weirdly seemed less oppressive.
Did Harribel get weaker? Of course not!
Toshiro got stronger.
Especially since Harribel generates water; fighting her only makes him stronger.
"There's heavy moisture here," Toshiro murmured. "So I could use Sennen Hyōrō so early. Hah… looks like I've got a long road."
"As long as you understand. Arrogance is strength's greatest enemy," Yoshio said. "You're very gifted. Keep it up."
He sheathed his blade, raised a hand, and used a healing wave to treat Toshiro's wounds.
"Let's go back."
They hadn't fought long; it was still early when they returned.
…
It was just a spar, so Toshiro didn't mind losing—he expected it, really.
He only wanted to see the gap—and it was large.
But that gap didn't dishearten him; it only fired him up to chase.
Seeing Toshiro so energized, Yoshio wondered if he was raising a little monster ahead of schedule.
Hitsugaya Toshiro truly was a prodigy. In canon, without going to the Royal Palace, he trained for just over a year and went from struggling against Grimmjow's fracción to restraining the Soul King's heart.
You could say most captains coast. Few train consistently.
Especially after becoming captain, people slack more.
Only after setbacks, after being pummeled by Aizen, do they recognize their weakness and resume training as challengers.
So yes—these people need to be beaten.
Guys like Yamamoto, Kyoraku, Ukitake, Unohana—old folks not training is one thing. They're either at their limit or in a bottleneck. A few years won't change much.
But younger captains slacking?
That's wrong.
Now, with Yoshio's prodding, Toshiro would make hard training routine. Maybe he'd achieve complete bankai a decade early.
Clicking his tongue, Yoshio stepped out for air—and saw Aizen arriving.
"Captain Aizen!"
Yoshio waved.
"So fast?"
"Once I finished work, I came," Aizen said, producing the Hogyoku. "I fixed some issues. You can resume testing."
Yoshio's eyes lit up. "Many thanks, Captain Aizen!"
He took it, already planning to test it at Las Noches.
A little later, Kyoraku Shunsui and Ukitake Jushiro arrived.
Yoshio had organized the dinner mainly to see how Ukitake's soul ability had changed.
Sure enough, his old soul power "Host" had become "Tranquil Rain."
"Tranquil Rain: calls down calming raindrops that greatly heal allies in a wide area."
?
Yoshio felt like that belonged to Division 4, but Ukitake's new power also pertained to healing.
Fitting…
After retiring, he'd mostly be "recuperating." A healing-related power was unsurprising.
Division 4 members actually had many combat-type abilities—that was tied to their "heart's wish."
Tranquil Rain was nice—an AOE heal. But raising Ukitake's favorability to 90 would be too hard.
So Yoshio didn't overthink it. He had Healing Wave, anyway.
After the captains ate, they left. As Yoshio was about to head to Hueco Mundo, Yamiko came by.
"I'm coming too," Yamiko said blandly.
She'd been at dinner too—the only non-captain present.
Kyoraku had tried to recruit her to Division 8, but Yoshio had sternly refused.
"What are you going to do there?"
"Kids should sleep early."
"I'm going," Yamiko insisted. "If you don't take me, I'll go myself."
Seeing her eyes, Yoshio surrendered. "Fine. But don't touch anything."
He was about to open a Garganta, only to see Yamiko raise her hand and tear one open.
"Hey, hey—I didn't give you the frequency. How are you opening a Garganta inside the Soul Membrane?" Yoshio asked.
Yamiko looked at him strangely. "I've watched you open so many. Watching was enough."
"…Right." Yoshio decided not to converse with such a little monster and stepped into her Garganta to Las Noches.
"You can play with Starrk and them now."
Once there, Yoshio took Yamiko to Starrk's room and knocked.
Starrk opened, surprised to see Yoshio and the girl. "This is…?"
"Yamiko, my cousin. She insisted on seeing Las Noches. Have Lilynette keep her company. I've got business," Yoshio said.
Starrk didn't object, and Yamiko went in.
With Starrk supervising, Yoshio relaxed and went straight to Szayelaporro's lab.
Szayelaporro welcomed him. He'd been helping research the Hogyoku and had prepared dozens of test subjects.
Yoshio got to work.
With Aizen's tweaks, the Hogyoku had higher completion and was smoother to use.
He tried Quincy-izing the first Arrancar. It failed eventually, but lasted much longer.
He adjusted the dose. The second subject changed.
Externally unchanged, still an Arrancar, but his reiatsu felt odd—faintly Quincy-like.
Yoshio was pleased, but before he could observe more, the subject self-destructed and lost form.
He didn't get discouraged; he continued.
By the 33rd, the subject stabilized, keeping form and steady aura.
"I see…"
Yoshio gained insight.
He'd been stepping too far.
He always wanted to break boundaries—but that isn't easy.
In canon, the only explicit limit-break via Hogyoku was Aizen.
While imparting Quincy-ization to Arrancar, he also analyzed the Arrancar's own Hollow Apotheosis.
He found it wasn't true limit-breaking.
Breaking limits would be truly fusing two kinds of souls, pushing past the limit, then reconstituting in a special state, creating a soul stronger than Shinigami and Hollow.
Arrancarization simply wrapped Hollow souls in a Shinigami-factor shell. There was some intermingling, but far from fusion.
If truly fused, even a Vasto Lorde's soul couldn't withstand the limit break.
Only those who reach soul-limit—like Aizen at the Shinigami limit—and force deeper "fusion" and "submission" from the Hogyoku in battle could complete soul reconstitution.
With a clearer grasp, Yoshio now covered the Shinigami-factor shell with another layer—Quincy factor.
Like dual rings.
Empty core: Hollow soul. First ring: Shinigami factor. Second: Quincy factor.
The three only partially intersect—no complex reactions.
"But then the Quincy factor is too sparse," Szayelaporro said. "It has to penetrate the Shinigami layer to affect the soul."
"True, but no choice," Yoshio sighed. "Souls are too fragile. We can't make big adjustments."
"If we could insert two partitions in the soul, we could put Shinigami factor in the middle and Quincy factor on the far side," Szayelaporro proposed. "That way, both act simultaneously on the soul."
Yoshio glanced at him. "A reishi partition? I can get you as many reishi baffles as you want. But a soul partition…"
Not easy. Souls are too fragile for such research.
Szayelaporro fell into troubled thought.
"I can help," a voice said suddenly.
Both men jumped; they'd been deep in thought, and the newcomer was silent.
Especially Szayelaporro, who snapped, "Who are you? Who allowed you into my lab?!"
Yoshio stopped him. "Yamiko, didn't I tell you to play with Lilynette? Why are you here?"
Yamiko ignored Szayelaporro and Yoshio's question. "I sensed your frustration. Need help? I can solve your problem."
"Who is she?" Szayelaporro asked coldly.
"My cousin," Yoshio said briefly. Then to Yamiko: "You can help? How?"
Yamiko looked at the 33rd subject. She went over and placed her small hand on his face.
The subject's reiatsu instantly grew serene. Yoshio's pupils tightened—he saw the soul's structure aligning exactly as he and Szayelaporro had imagined!
Szayelaporro's instruments confirmed it. "What did you do?!"
Yamiko glanced at Yoshio, who also looked puzzled. "I gave him a soul partition. That's all."
?!
Yoshio's eyes widened.
"Yamiko, are you…" He was shocked. "Are you an Incomplete?"
Granting power and properties to others—that's Yhwach and Haschwalth's ability!
Yamiko… could use it?
"I don't know what an 'Incomplete' is, but I can use the power of bestowal," Yamiko said lightly.
Yoshio stared at her—and suddenly grasped Aizen's true aim.
Damn…
Aizen wasn't trying to make a Soul King candidate. He was trying to make a Soul King's child!
Yes—he wanted to make a Yhwach!
Aizen's gone mad—he wants a new Wandenreich!
With Quincy data parsed, Aizen would know about special Quincy like Haschwalth and Yhwach.
But…
How did he make an Incomplete?
Yoshio frowned, then…
Could Yamiko's power be imagined into being?
If Gremmy could make thoughts reality, then if you set the brain in the vat is an Incomplete as a property, could it simulate such traits?
He didn't know Aizen's exact method, but he now roughly understood Yamiko's make.
Yamiko was Aizen's virtual Yhwach.
And Aizen's ultimate goal was to turn this virtual Soul King's daughter into a real Soul King's daughter.
So he placed Yamiko by Yoshio—the Soul King fragment in his eyes?
So far…
Aizen's plan was working.
Yamiko's growth was rapid. She'd now simulated the Incomplete's Bestowal—though it was a negative buff that constantly drained her soul.
No matter; Aizen never lacked test subjects. If Yamiko's soul waned, he'd find more material to feed her.
If she could simulate Auswahlen, then Aizen's experiment would be a complete success.
If Yamiko then devoured lots of Soul King fragments, her status as Soul King's daughter would be cemented.
Wait—then what would that make me, the Soul King's daughter's cousin?
I haven't even gotten Tsukishima Shukuro's "Big Cousin" ability yet!
Another thought struck Yoshio.
If…
If he used Big Cousin on Yhwach, he'd become Yhwach's cousin. What status would that give him?
His cousin is the Soul King's son; his cousin is the Soul King's daughter?
In this world, "names" matter. Titles matter.