Kaien Shiba Under Watch

Jūshirō Ukitake said gently to Kaien Shiba, "Kaien, then I'll trouble you to go to the World of the Living and reassure the Quincy, so as to avoid any unnecessary misunderstandings."

"Yes, Captain." Kaien Shiba replied respectfully, then turned and left the Thirteenth Division's barracks. His steps were steady, but a sense of unease lingered in his heart—from the conversation just now, he realized that things were far more complicated than they appeared on the surface.

After Kaien Shiba left, Unohana also bid farewell to Jūshirō Ukitake and returned to the Fourth Division. Only Ukitake remained in the courtyard. He sat by the stone table, gazing at the tea in his cup that was gradually cooling, lost in thought.

Just then, a gentle and familiar voice came from the courtyard entrance. "Captain Ukitake, what are you thinking about all alone here?"

Jūshirō Ukitake looked up and saw Sōsuke Aizen standing in the moonlight, his face bearing that signature gentle smile. He was wearing the haori of the Fifth Division Captain, looking like an ordinary visitor, but Ukitake's heart suddenly rang with alarm bells—he remembered Captain-Commander Yamamoto's words. "We have enemies within our ranks."

"Captain Aizen, what brings you here?" Ukitake stood up, maintaining a polite smile.

Aizen walked slowly into the courtyard and sat down at the stone table. "Nothing much, just came to see you. How have you been lately?"

Ukitake sat down again and poured Aizen a cup of tea. "Not bad, the illness is under control."

"That's good," Aizen, taking the teacup and gently blowing on it. "Captain's poor health Ukitake isn't feeling well; he needs to rest more. If you need any help, feel free to contact me anytime."

Ukitake smiled and said, "Yes, it's fortunate that Kaien is here. He handles many things for me. Once he's grown up, I should be able to retire."

"Vice-Captain Kaien is indeed a good successor," Aizen's gaze seemed to casually sweep towards the direction of the courtyard entrance, "But he's been going to the World of the Living quite often lately, is something wrong? Should we transfer some people from my place to help him?"

These words sounded like concern, but Ukitake keenly sensed a hint of probing. He maintained his smile and said naturally, "It's just a small matter; Kaien can handle it."

Aizen took a sip of tea, then said seemingly casually, "A few days ago, some Menos Grande appeared in the World of the Living, and they seem to have been dealt with by some unknown Soul Reaper. However, based on the information I received, I think it's very likely that it was Lieutenant Liu Hao. Only he has the strength to easily deal with those Menos Grande."

Ukitake tapped his fingers lightly on the table, his smile unchanged, "How did Captain Aizen determine it was him? There might be some hidden masters in the World of the Living too."

"I'm not sure," Aizen shook his head. "He just said the Reiatsu is unfamiliar, and there's no relevant information in the Seireitei's files. It's best for the Seireitei to monitor someone like that; if he has malicious intent, he could cause irreversible damage to the World of the Living."

His tone carried a measured concern, perfectly befitting a responsible Captain. But Ukitake knew that there might be a deeper intention hidden behind those words.

"Captain Aizen is overthinking it," Ukitake said with a smile. "According to the information from the Second Division's Stealth Force, that person, although very strong, is also very restrained. He must be worried about any negative impact on the World of the Living."

Aizen nodded, his expression returning to ease. "I hope I'm just overthinking it. But since Vice-Captain Kaien is going to the World of the Living, we can let him investigate while he's at it, since we don't know what the other side is really thinking."

Ukitake's heart skipped a beat; Aizen seemed particularly concerned about Kaien Shiba's journey to the World of the Living. However, he didn't show it, simply saying calmly, "Yes, I'll have Kaien keep an eye on it."

The two chatted about their respective squads for a while, and the atmosphere seemed harmonious. About half an hour later, Aizen stood up to say goodbye, "It's getting late, so I won't disturb Captain Ukitake's rest any longer."

"Captain Aizen, take care." Ukitake stood up to see him off.

As Aizen's figure disappeared into the night, Ukitake's expression turned solemn. He returned to the stone table, sat down again, and unconsciously tapped his fingers on the surface.

[Why is Aizen so interested in Kaien's actions?] Ukitake wondered to himself, [Could it be that he really is as the Captain-Commander said...?]

He dared not think any further. If Aizen was indeed an enemy hidden within the Gotei 13, what did that mean? It meant that all the discussions at the Captains’ Meetings, all the strategic plans, might have been leaked.

As night deepened, the chirping of insects in the courtyard became exceptionally clear. Ukitake knew he needed to be even more careful—not only for himself, but also for those who trusted him.

Meanwhile, instead of returning to the Fifth Division Barracks, Sōsuke Aizen went to a secret laboratory in a secluded location in the Seireitei. When he opened the door, Gin Ichimaru and Kaname Tōsen already waiting there.

The laboratory was filled with sophisticated instruments and displays, one of which showed real-time footage of Kaien Shiba moving through the World of the Living.

"So, Captain Aizen, did you get any useful information?" Gin Ichimaru asked, his eyes narrowed and a cryptic smile on his face.

Aizen sat down at the control panel, looking at Kaien Shiba on the screen. "No. As expected of Captain over a hundred years old, he seems to be wary of me."

Kaname Tōsen turned towards Aizen; though he couldn't see him, his other senses were exceptionally sharp. "Since Kaien Shiba might be in contact with Liu Hao in the World of the Living, shouldn't we deal with him?"

Aizen softly, a cold glint flashing in his eyes. "Yes, but don't be in such a hurry. Perhaps we can find Liu Hao through him, or even Kisuke Urahara and the others."

The three watched the screen in silence. On the screen, Kaien Shiba was walking through the streets of Karakura Town, heading towards Kurosaki Clinic. His route was clear, and he seemed to have a well-thought-out plan for his destination.

However, at that moment, the image on the screen suddenly distorted and then turned into static. All signals were interrupted, and the monitoring equipment in the laboratory lost its target.

Aizen showed no surprise, instead revealing a meaningful smile, "It seems someone doesn't want us to know they've made contact. But such an obvious move, doesn't it tell us they're in contact?"

Gin Ichimaru's smile widened, "Maybe he wants to go fishing, who knows?"

Kaname Tōsen frowned. "Should we go to the World of the Living and get rid of those rats?"

Aizen shook his head, stood up, walked to the window, and gazed at the night view of Seireitei outside. "No need. Just like Gin said, he's telling us that he knows we're monitoring Kaien Shiba. If we go out now, we'll definitely fall into his trap. After all, that person's intelligence is above ours."

"Liu Hao?" Gin Ichimaru asked.

"Or Kisuke Urahara," Aizen turned around, his eyes deep, "Or the two of them together. Either way, they should not be underestimated."

A brief silence fell over the laboratory. All three understood that this covert contest had entered a new phase. Their opponent had not only discovered their surveillance, but had also retaliated in this way—a provocation, and a declaration.

"So what do we do next?" Kaname Tōsen asked.

Aizen sat down again, his fingers lightly tapping the control panel. "Wait. Sometimes, the best action is inaction. Let them think we've backed down, lower their guard. Then..."

He didn't finish speaking, but Gin Ichimaru and Kaname Tōsen understood his meaning. Waiting in the shadows, striking at the most unexpected moment—this was Aizen's most adept tactic.

"However," Aizen suddenly said, "We need to confirm one thing. That insect was discovered, but who discovered it? Was it Liu Hao, or Kisuke Urahara? Or someone else?"

This question plunged the laboratory into deep thought once again. Monitoring insects was Mayuri Kurotsuchi's technology, and although it had been improved by Aizen, it was essentially still a product of the Twelfth Division's technology. The fact that they could detect and remove it so quickly indicated that the other party had a very good understanding of this type of technology.

"Kisuke Urahara is more likely," Gin Ichimaru analyzed. "After all, he was the Captain of the Twelfth Division and knows Captain Kurotsuchi's techniques best."

Aizen nodded. "That's possible. But we can't rule out the possibility that Liu Hao himself possesses this ability. After all, he's someone we still can't fully understand."

Outside the window, the night in Seireitei deepened. On this seemingly peaceful night, an invisible struggle was unfolding on multiple levels.

In the World of the Living, on a street in Karakura Town.

Kaien Shiba was moving rapidly through the air, heading towards Kurosaki Clinic. However, as he flew over a commercial district, the surrounding scenery suddenly changed—streets, buildings, lights—everything became blurry and distorted, as if shrouded in a transparent veil.

He was startled and immediately drew his Zanpakuto from his waist, cautiously looking around. He was familiar with this spatial anomaly; it was some kind of barrier or domain-like ability.

"Who's there?" Kaien Shiba asked sharply.

"Kaien, don't be so nervous." A familiar voice came from beside him.

Following the sound, Kaien Shiba saw a figure draped in a black cloak slowly emerge from the void. Although the figure's face was mostly obscured by the cloak, Kaien Shiba immediately recognized him— Liu Hao.

"So it was you," Kaien Shiba breathed a sigh of Zanpakuto. "This is the power of your Zanpakuto, isn't it? Why did you suddenly attack me?"

Liu Hao walked up to him, lifted the hood of his cloak to reveal that familiar face. "You're being watched. I have no choice but to isolate you like this to prevent others from spying on you."

Kaien Shiba was shocked. "How is that possible? When I went back, I only interacted with our Captain, the Captain-Commander, and Captain Unohana."

"It wasn't them," Liu Hao shook his head. "Only Mayuri Kurotsuchi and Aizen could use such methods to monitor you."

As he spoke, Liu Hao walked up to Kaien Shiba and placed his hand on his shoulder. Kaien Shiba instinctively tried to back away, but Liu Hao was faster—his hand emitted a soft, milky-white light, and then it actually "reached" directly into Kaien Shiba's body.

This scene horrified Kaien Shiba. Just as he was about to break free, he saw Liu Hao pull his hand out, holding a black, rice-grain-sized worm between two fingers. The worm was still wriggling slightly, its surface covered with complex Reishi patterns.

"What is this?" Kaien Shiba asked, frowning, a wave of nausea rising within him.

"A monitoring insect," Liu Hao held the insect up to his eyes for close examination, "Placed inside your body without your knowledge. It was because I sensed an unusual Reishi emanating a special Reiatsu within your body that I deduced you were being watched."

After Liu Hao finished speaking, he took out a small metal box, put the insect inside, and then applied several layers of sealing Reiatsu. The insect struggled a few times inside, but eventually calmed down.

Kaien Shiba watched this scene, a wave of fear washed over him. If this worm had remained inside his body, then all his actions and conversations could have been monitored by the person behind the scenes.

"How can you still be so calm?" Kaien Shiba asked, looking at Liu Hao's composed expression.

Liu Hao raised an eyebrow. "Hmm? Why aren't you calm?"

"They're monitoring my movements, they must suspect me," Kaien Shiba said anxiously. "By coming out like this, even though you've avoided being monitored, it will still let them know I've made contact with you. Won't that allow them to discover your information?"

Liu Hao smiled, a confident and composed expression on his face. "Don't worry. If it's Mayuri Kurotsuchi, he'll go directly to your Captain to ask for information. If it's Aizen, he won't show himself easily. After all, in his view, the only person who can interfere with his technology is Kisuke Urahara, and someone as exceptionally intelligent as Kisuke Urahara certainly won't expose his whereabouts so easily."

He paused, then continued, "So he'll only verify this through others; otherwise, he'll fall into the trap Kisuke Urahara has set for him. So we don't need to rush at all."

These words reassured Kaien Shiba somewhat, but he was still worried. "But is this really alright? Aizen, that person..."

"Aizen is indeed very dangerous," Liu Hao's expression turned serious, "But it's precisely because he's dangerous that he's more cautious. He won't act without complete certainty. And we can take advantage of that."