Orihime Inoue's heart tightened as she thought of the possibility Rukia Kuchiki had just described.
Rukia Kuchiki pressed her lips together.
Before this, she had been thinking of asking Retsu Unohana to help persuade Muten Natsu to give up that dangerous plan.
But now she understood clearly that the invasion of Hueco Mundo could no longer be stopped.
The fundamental reason the invasion of Hueco Mundo had become inevitable was the existence of Negación.
As long as Negación existed, the Arrancar who came to the World of the Living could retreat at any time.
That meant the Arrancar could invade the World of the Living again and again without having to worry about losses.
But the Shinigami were different.
On one hand, in order to defend against Arrancar invasions in time and prevent them from causing too much damage, Shinigami had to remain on standby in the World of the Living.
But if too few came, they could not hold them off. If too many came, Soul Society's defenses would be left hollow.
The Shinigami who came to the World of the Living were in danger, and the Shinigami in Soul Society were not safe either.
The Arrancar could fail countless times, but as long as they succeeded once, they could cause enormous damage. Whether that damage was done to the World of the Living or to Soul Society, it would still be a success for Sōsuke Aizen.
On the other hand, Sōsuke Aizen could use the Hōgyoku to turn the Hollows of Hueco Mundo into Arrancar, rapidly transforming them into usable combat forces.
By contrast, even after long periods of study and grueling training, the Shinigami of Soul Society still struggled to reach the level needed to oppose the Arrancar.
As one side grew stronger and the other weaker, the longer this dragged on, the lower their chances of victory became.
Most importantly, once Sōsuke Aizen's plan began, the Espada, who possessed top-tier killing power, would scatter in every direction around Karakura Town.
To protect the World of the Living, the Shinigami would have no choice but to go and stop them.
Once battle broke out, whether the Shinigami won or lost, powerful souls would perish, and Sōsuke Aizen could use that to achieve his goal.
They could not build up strength and wait for a decisive battle. They could not allow Sōsuke Aizen's plan to begin. That left only one option: invade Hueco Mundo.
"It looks like this is the only way," Tōshirō Hitsugaya said, his brow tightly furrowed. "But is it really a good way?"
Rangiku Matsumoto looked puzzled. "Captain?"
"Are we choosing this method because we have no other choice, or because Sōsuke Aizen wants us to choose it?" A cold glint flashed through Tōshirō Hitsugaya's eyes. "That determines whether this operation is a surprise attack that catches him off guard, or whether we're being forced to walk right into his trap."
"Obviously..." Kisuke Urahara opened his folding fan. "It's the latter."
Tōshirō Hitsugaya's frown deepened. "Then this operation will be extremely dangerous. Captain-Commander, I request permission to participate in the invasion of Hueco Mundo."
"You will remain stationed in the World of the Living in case of emergencies." Genryūsai Shigekuni Yamamoto rejected Tōshirō Hitsugaya's request. "The members for the invasion of Hueco Mundo have already been chosen."
An antique circular paper sliding door appeared out of thin air, and several Jigokuchō brought the Shinigami through.
At the front was 4th Division Captain Retsu Unohana, smiling gently. When Muten Natsu looked at her, her smile grew even softer.
6th Division Captain Byakuya Kuchiki stood expressionless with his eyes slightly closed. When he opened them, his gaze swept over Rukia Kuchiki before landing on Renji Abarai.
Renji Abarai looked away from him with some guilt. He should have taken part in the previous battle too, but the toll from his training had been too great, leaving him unable to participate.
That was a serious dereliction of duty.
11th Division Captain Kenpachi Zaraki rested his left hand casually on his collar while scratching the side of his face with his right. Before he had even stepped out of the door, he was already giving Muten Natsu a savage grin.
Everyone else looked much the same, but 12th Division Captain Mayuri Kurotsuchi was different.
His face, which had originally been completely black, now had white cheeks. His nose, which had only been slightly white before, was now white along with the bridge of his nose and the space between his brows, and there was also a white patch on his chin.
The parts that should have been his ears were still shaped like conch shells, but their color had changed from yellow-brown to golden yellow. A golden frame extended around his entire face, and his formerly white teeth had also turned gold. His purple lapels were still there, but now he had a dark-blue hat shaped like a croissant.
He had already been strange enough before, but now he looked even stranger.
Accompanying Retsu Unohana were Lieutenant Isane Kotetsu, and the assistant aide, Captain of the 14th High-Level Medical Unit and 7th Seat of the 4th Division, Hanatarō Yamada.
"Hana-chan!" Yachiru Kusajishi poked her head out from Kenpachi Zaraki's shoulder. "And Big Boobs and Ruki-Ruki!"
Orihime Inoue's raised hand froze in midair.
Rukia Kuchiki's expression turned complicated. It was not the first or second time Yachiru Kusajishi had called her Ruki-Ruki, so why did it feel so wrong this time?
Nemu Kurotsuchi followed behind Mayuri Kurotsuchi as silently as ever.
Byakuya Kuchiki stood alone.
Renji Abarai dared to look at him even less.
"As Hitsugaya said, this invasion of Hueco Mundo is indeed walking into a trap. This mission will be fraught with difficulty, and victory is far from certain..." Genryūsai Shigekuni Yamamoto's aged eyes opened. "But that is the very reason the Gotei 13 exists. When faced with a crisis, we advance whether we have a solution or not!"
"So we just cut down everything we see, right?" Kenpachi Zaraki grinned ferociously. "What difficulty? That sounds like pure enjoyment to me!"
"There are difficulties," Mayuri Kurotsuchi said, glancing at Kisuke Urahara. "He still hasn't managed to finish dealing with the Garganta even now. It seems someone has run into a monumental problem, ne~"
"The Garganta has already been opened," Kisuke Urahara said, waving his folding fan. "Its stability just isn't enough to support Captain-class passage yet."
"If you want to improve stability..." Mayuri Kurotsuchi raised a hand. "Why not use Hollows? Is it that you don't want to... or that you simply didn't think of it?"
Behind Mayuri Kurotsuchi, Nemu Kurotsuchi cooperatively opened the case in her hands. Inside were several tube-shaped containers, each filled with culture fluid and a small, damaged Hollow floating within.
Byakuya Kuchiki's voice barely fluctuated. "Mere Arrancar."
Retsu Unohana only smiled without speaking.
"At a time like this, you're supposed to answer the call and say something more passionate." Muten Natsu glanced at the screen. "If you give him this little support, the old man looks kind of pitiful."
Orihime Inoue tugged at the corner of Muten Natsu's clothes.
At first, no one had thought much of it, but after Muten Natsu said that, everyone suddenly felt that Genryūsai Shigekuni Yamamoto did look a little pitiful.
"Muten Natsu..." Genryūsai Shigekuni Yamamoto's grip tightened on his cane. "Sōsuke Aizen's target is the World of the Living. Soul Society's power alone may not always be enough. I know how you feel about Soul Society..."
"No, you don't," Muten Natsu cut him off. "If you did, you would understand that what I want to protect has never changed from the very beginning."