Self-Arrancar

"Shopkeeper, I'm back," Tsuna called as he pushed open the doors of Urahara Shop.

"Tsuna, my boy, what brings you here? Or have you taken a fancy to something in my shop?" Urahara Kisuke emerged with a laugh.

"If there'd been anything worth buying, I would've bought it long ago. Where's everyone else?"

"They went to the warehouse with Tessai to restock," Urahara replied.

"Perfect. I need your help with something."

"My services are quite expensive, you know," Urahara said, pretending to make things difficult.

"That's fine. Put it on Ichigo Kurosaki's tab." Tsuna called outside, "Inoue's Brother, come in."

Sora Inoue's soul drifted into Urahara Shop. When he had first arrived, he hadn't wanted to enter; his instincts told him this place was extremely dangerous.

"A spirit body? You shouldn't need me for Konso, should you?" Urahara asked, lowering the brim of his hat slightly.

"Here's the situation..." Tsuna told Urahara Kisuke everything about Sora Inoue's choice.

"Become a Hollow? His obsession is that strong?" Urahara circled Sora Inoue once. "Forgive my bluntness, but there's no point. Hollows are souls transformed by the void in their hearts. Once they lose their hearts, retaining their sanity is nearly impossible."

Urahara turned to Tsuna. "Tsuna, my boy, I have more authority than you in this matter. Perform Konso."

"For an ordinary soul, sure, it would be pointless. Shopkeeper, a word." Tsuna pulled Urahara Kisuke into a corner. "But what if Inoue's Brother has the potential to become a Self-Arrancar?"

"Arrancar?" Urahara raised an eyebrow, immediately intrigued. "Interesting term. A Hollow that breaks its mask?"

"That's right. He's one of only two Hollows in history who might become a Self-Arrancar. Otherwise, I wouldn't have agreed to help him." Tsuna had decided to bring Sora Inoue to Urahara Kisuke because, in the original story, Sora Inoue had been moved by Orihime Inoue and broken his Hollow mask on his own.

"Only two? Then the other Self-Arrancar Hollow..."

"Probably the strongest in Hueco Mundo. So? Interested, Shopkeeper?" Tsuna asked.

"Potential to become one of Hueco Mundo's strongest? That is worth trying." Urahara murmured, then told Tsuna solemnly, "This assistance will be free of charge, but you'll have to bear the consequences of the experiment yourselves."

"Of course. I already warned him."

"Sora Inoue, correct? Please come with me."

Urahara tapped his cane, and a hidden passage appeared in the wall beside them. Tsuna and Sora Inoue followed Urahara Kisuke inside. After passing through a long, dark tunnel, they arrived in a room filled with instruments. It appeared to be Urahara Kisuke's laboratory.

Urahara activated a machine, and a huge tank lit up. Inside was a mass of unknown white flesh, resembling something from within a Hollow's body.

"Inside is pure Hollow flesh that I extracted. Go in and touch it with your spirit body. It will enter your spirit body, and then you'll begin transforming into a Hollow." Urahara pointed at the tank, where he had already opened an entrance for Sora Inoue.

Sora Inoue glanced at Tsuna. "Orihime is in your care, Tsuna."

Tsuna waved him off, clearly refusing to take the bait. "Take care of your own sister. Remember Orihime Inoue, then survive."

Sora Inoue bowed respectfully to both of them, then threw himself into the tank without hesitation. The instant he entered, Hollow power began eroding him. The Causal Chain on his chest vanished at once, and a hollow hole appeared in his chest.

Agonized screams came from within the tank. Large amounts of white fluid erupted from the flesh and completely swallowed Sora Inoue. Twisted limbs spread out from his body as he began transforming into a Hollow.

"Tsuna, my boy, you don't seem surprised by anything in this place," Urahara remarked casually as he pressed a strange button.

"With all the cutting-edge technology you've mastered, how could you not have your own lab?" Tsuna said.

"I thought you would be rather opposed to this sort of experiment." Urahara looked at Tsuna.

"Well, if possible, I'd still hope you'd show a little more respect for life in your experiments, Shopkeeper." Tsuna did not dwell on the matter. Instead, he drew his Zanpakuto and recited the release command for his Mist-type Shikai.

A Trident appeared in Tsuna's hand. He watched Sora Inoue in the tank closely, ready to act at any moment.

"Tsuna, my boy, watch my equipment. Don't smash anything..." Urahara hurriedly said. Every instrument here was valuable. If Tsuna started fighting in here, his laboratory would not survive the damage.

"Relax. I'm not going to fight. I'm just taking precautions." Tsuna rested the Trident against a nearby table, showing no intention of wrecking the place.

As time passed, the Hollow in the tank gradually took shape. It looked exactly like the Hollow Sora Inoue had become in the original story: a humanoid body with a snake tail, Sora Inoue's hairstyle behind its mask, and a color scheme dominated by gray and orange-red.

And just like in the original story, Sora Inoue had now completely lost his sanity. He had become a Hollow that knew only how to devour, repeatedly slamming into the tank in Urahara and Tsuna's direction.

"Looks like it failed, Tsuna, my boy." Urahara's tone did not change at all. Failed experiments were common; he had long passed the age of having his emotions stirred by them.

"No. Let me add a little something!"

Tsuna kicked out, and the Trident flew into his hand. He had long prepared for Sora Inoue's failure. Now it was time to bring out the backup plan he had prepared.

As Tsuna slammed the Trident heavily against the ground, Sora Inoue's world changed. This was no longer Urahara Kisuke's laboratory, but the modest home where the Inoue siblings had relied on each other. Within that home, Orihime Inoue looked gently at Sora Inoue.

"Brother, you're home?"

Just as she always had when welcoming Sora Inoue home, Orihime Inoue smiled and approached him. It was as though she could not see his monstrous form, raising her hand to take the briefcase he carried.

His vision blurred, and Sora Inoue saw another version of himself, exhausted from the day, handing his weariness over to Orihime Inoue and sharing the day's experiences with her.

That scene, so ordinary it could not have been more ordinary, calmed the frenzied Sora Inoue. He did not know why he had stopped moving. He only felt that he should quietly protect this scene.

A cold voice pierced the illusion and struck directly at Sora Inoue's mind. "Sora Inoue! Remember! What matters most to you—Orihime Inoue!"

Under Tsuna's warning, the cloudiness in Sora Inoue's eyes gradually cleared. He muttered, "I... Inoue... Sora..."

The scene shifted again. A timid little girl appeared before Sora Inoue. It was Orihime Inoue as a child. Then an Orihime of her current age appeared on his left, while a high-school-aged Orihime Inoue appeared on his right.

Orihime Inoue from one stage of life after another appeared around Sora Inoue, surrounding him. Tsuna had created these different Orihimes from his own memories. Each wore a different expression, and every cry of "Brother" made Sora Inoue's gaze grow firmer.

At last, all those Orihime Inoues faded into the darkness. An Orihime Inoue dressed in a White Kimono appeared before Sora Inoue. She pointed sweetly at the ornament on her head and asked, "Brother, can you put on my Tsunokakushi for me?"

With a crack, a fissure split across Sora Inoue's Arrancar mask. As the image of Orihime Inoue's future life appeared, more and more cracks spread across the mask. When every version of Orihime Inoue appeared once more, Sora Inoue's mask shattered completely, revealing his somewhat relieved face.

The different versions of Orihime Inoue around him fulfilled the obsession Sora Inoue had held at death—to witness Orihime Inoue's growth. Because that obsession had been fulfilled, he had truly completed his Self-Arrancar transformation.

"Truly interesting," Urahara Kisuke commented.

Urahara had watched Tsuna's entire process. To be honest, he had not believed it would succeed at first. Yet this Hollow had truly become a Self-Arrancar and regained Sora Inoue's sanity. Driven by curiosity, he even felt like getting his hands on him for some experiments, though he still had to watch Tsuna's reaction.

"Congratulations, Inoue's Brother." Tsuna withdrew his Zanpakuto and spoke to Sora Inoue.

"Thank you very much, Lord Tsuna, Lord Shopkeeper." Sora Inoue spoke with great respect. He knew that he could not have returned to normal without these two.

"It's too early for thanks. You've become a Hollow now. Though you can retain your sanity and won't fade away, with your current strength, you still can't freely go see Orihime. You might even be dealt with by someone at any time."

"Focus on getting stronger first. Once you're stronger, you can return to a normal human form. It'll be much more convenient to see Orihime then, won't it?" Tsuna dangled the prospect before Sora Inoue.

"I'll trouble you, Lord Tsuna." Sora Inoue bowed.

"Not me. Lord Urahara." Tsuna turned to the side. "Shopkeeper, is it fine to leave Inoue's Brother with you? You've been itching to get your hands on him for a while now."

"Oh? Tsuna, sir, aren't you afraid I might perform some strange experiments on him?" Urahara had not expected Tsuna to be so perceptive that he had even noticed his eagerness.

"If possible, help Inoue's Brother evolve toward the Adjuchas level first. In return, I think it's a fair exchange for you to obtain some experimental data," Tsuna said. He truly had no ability when it came to Hollow evolution.

Sora Inoue fully displayed the perceptiveness he had developed as an office worker in life. He immediately turned to Urahara Kisuke, curled up respectfully, and said, "Please, Lord Urahara!"

"All right, then. Let us begin an interesting experiment." A pleased smile lay beneath Urahara's folding fan.

"That settles it, then. Shopkeeper, I'm heading back. Ichigo and the others are urging me to return." Tsuna held up his phone.

Before leaving, Tsuna had specifically messaged Tatsuki and asked her to distract Orihime Inoue for a while. Tatsuki and Ichigo had barely left Inoue's House before impatiently messaging him.

Urahara tapped his cane again, and a hidden passage appeared. "I won't see you off, Tsuna, sir."

After meeting up with Tatsuki and Ichigo, Ichigo immediately asked impatiently, "Tsuna, where did you go? And Inoue's Brother—how is he?"

Even someone as simple-minded as Ichigo could guess that Tsuna's sudden disappearance meant Sora Inoue had not simply passed on.

"Wait a little longer. Once your Fullbring begins to show results, I'll take you to see him," Tsuna said.