A New Zanpakutō  

Izuru Kira didn't know why Gin Ichimaru had betrayed the Soul Society. But unlike the other members of the Third Division, he didn't feel betrayed.

He owed everything to Gin. Gin had taken him under his wing, guiding him and nurturing his talents.

Even when Gin had provoked Momo Hinamori, leading her to draw her sword against him, Kira, despite his reluctance to fight a friend, had stepped forward to defend his captain.

A lieutenant was a captain's shield. To allow his captain to be injured while he was still able to fight was a disgrace. He believed it, and he had acted accordingly.

He paused, his pen hovering over the report. Why was he dwelling on the past? He shook his head and returned to his work. A lieutenant was a captain's right hand.

Every lieutenant was personally chosen by their captain. He knew that when the new captain arrived from Hueco Mundo, he would bring his own lieutenant. Kira's position was uncertain.

But he felt no resentment. He had failed as Gin's lieutenant. Still, as long as he held the position, he would fulfill his duties, leaving nothing for the new captain to deal with. Gin had always disliked dealing with paperwork.

A shadow fell over his desk. He looked up. "Captain Ailin?"

"I thought Lieutenant Hinamori was a hard worker, but seeing you, Lieutenant Kira, I realize she still has much to learn."

Kira flustered, unsure how to respond. The words seemed like a compliment, but what about Hinamori? Would she be reprimanded? As fellow lieutenants abandoned by their captains, he felt a certain kinship with her.

"I'm just teasing," Ailin said, sensing Kira's discomfort. "Lieutenant Hinamori is exhausted, so I gave her three days of paid leave."

"Thank you, Captain Ailin."

"That's interesting. I give my lieutenant a vacation, and you thank me."

"Captain Ailin," Kira asked, changing the subject. He was uncomfortable with Ailin's teasing. "What brings you here?"

Captains rarely left their divisions, especially newly appointed ones. Why would Ailin visit the Third Division instead of focusing on his own?

"I came to thank you."

"Thank me?"

"Yes. For taking care of my… wayward disciple for all these years."

Kira's mind raced. Which disciple? Ailin had several, but the only ones Kira had interacted with were Gin and Rukia. He had met Rukia through Renji Abarai, a classmate from the Shin'ō Academy.

They had remained friends, occasionally meeting after graduating. But Ailin wouldn't say he had taken care of Rukia. That left only Gin. But that didn't make sense. Why would Ailin say that Gin had been under his care?

"Captain Ailin," Kira began, about to question him, but Ailin interrupted.

"Lieutenant Kira, the moon is beautiful tonight. Shall we take a walk?"

…

Under the moonlight, with the Third Division members asleep in their barracks, Ailin and Kira walked along the corridors, the shadows of trees dancing on the walls, occasionally falling across their faces.

"Gin has been with me since he was a child," Ailin began, Kira falling silent, listening respectfully. Ailin spoke of Gin's past, a side of him Kira had never seen.

"He carries a heavy burden, a desire to protect those he cares about, but a constant fear that he lacks the strength to do so. He has dedicated his life to honing his skills. Without you, the Third Division would have fallen apart long ago."

He paused. "Kira, I know you're confused about why Gin joined Aizen. But I ask you to trust him. We shouldn't judge a person solely by their actions, but by the reasons behind them. Every action has a cause and a consequence. I won't speculate on why Gin sided with Aizen. I'm more interested in what drove him to such extremes, what burden he carries that forced him to stand against me."

He looked at Kira. "You're someone Gin values. He may be gone, but you're still here. Kira, I need you to take care of the Third Division for him."

Kira hesitated. "Captain Ailin, I appreciate your confidence in me, but my hands are tied. Captain-Commander Yamamoto has already issued orders. A new captain will arrive soon. Even if I wanted to protect the Third Division for Captain Ichimaru, I wouldn't be able to."

A captain's authority was absolute. Kira's position as lieutenant was uncertain. He might even be replaced. Thankfully, besides the lieutenant position, all other seated officer ranks were based on merit. He was confident in his skills. Even if he lost his lieutenant's badge, his position as Third Seat was secure.

"Kira, I'm not asking you to defy the new captain. I'm asking you to protect yourself, and your squad. You are all Gin's subordinates. I don't want him to return and find no familiar faces in the Third Division."

Kira's eyes widened. "Captain Ailin… are you saying… Captain Ichimaru will return?" His voice, filled with a desperate hope, rose slightly, breaking the quiet of the night.

Ailin sighed. "No, Lieutenant Kira. You must have misheard."

"But… I clearly heard…"

A sharp blow to the head sent Kira crashing through a wall.

"Who's there?" Shinigami on patrol rushed towards the sound, finding Ailin and Kira amidst the debris.

"Captain Ailin? Lieutenant Kira? What happened?" They looked at Ailin, then at Kira, unsure how to react. As members of the Third Division, their loyalty lay with their lieutenant. But Ailin was a captain…

"It's nothing," Ailin said calmly. "Someone asked me to look after the Third Division. I was just… checking on things."

The Shinigami exchanged confused glances. Who could have asked Captain Ailin to look after their division? And who had the authority to make such a request? They could only think of one person… but he was… gone.

Ailin said. "Return to your patrols. I need to speak with Lieutenant Kira."

As the Shinigami dispersed, Kira emerged from the rubble, his head throbbing. He had been careless, almost revealing Gin's potential return.

If Aizen learned of it, Gin would be in danger. While Aizen had left, his influence remained. Those he had hypnotized, and those who had willingly joined him, were still in the Seireitei.

The Shinigami who had attacked the nobles were just the most visible of Aizen's pawns. There were others, hidden in the shadows, perhaps unaware of their role in Aizen's plan.

"Draw your sword, Lieutenant Kira. Let me see what Gin saw in you."

…

As dawn broke, Kira lay on the training ground, gasping for air.

'Captain Ailin… he's even stronger than Captain Ichimaru… And his mastery of Zanpakutō abilities… it's beyond anything I've ever seen. After a single night of training, I feel… three times stronger!'

He wasn't referring to his spiritual pressure. Even Ailin couldn't significantly increase a Shinigami's reiatsu without external aids like Urahara's or Kurotsuchi's inventions, such as a reiatsu amplifier.

He was referring to his understanding and application of his Zanpakutō's abilities. Before, he had simply used Wabisuke to weigh down his opponent's weapons, forcing them to disarm. Or he would target their limbs, immobilizing them with gravity.

But after Ailin's guidance, he realized how… inefficient his methods had been. Even Ailin had admitted that if he possessed Wabisuke's power, his own strength would increase several times over. Wabisuke's ability, whether for training or combat, was exceptional.

…

"Wabisuke…"

Ailin walked back to his barracks.

"I had almost forgotten about that… unique Zanpakutō. I could use its ability to create a gravity blade, like Fujitora's. Perhaps, by training under increased gravity, I could further enhance my physical strength…"

The thought excited him. Any opportunity to improve his power was a welcome challenge. It meant he still had room to grow. He dreaded the day he reached his limit.

With the gravity blade, he could focus on pushing his physical abilities to their peak.

He wasn't sure how much Kira would improve. While Wabisuke's power was impressive, its limitations were also clear. It could only increase weight, not decrease it.

If Kira were stronger, if he could achieve Bankai, perhaps Wabisuke's power would evolve. But sadly, Kira lacked the potential…