Second Stage Bankai? Hollowfication!  

"The composition of this spatial power is quite impressive..." thought Ailin as he traced the invisible boundaries of the pocket dimension.

"However, it's far too fragile before me."

With a light tap on the air, a golden glow emanated from Ailin's hand. The power of the King's Key, bending space to his will. He thrust his hand forward.

Crack, crack...

The space before him shattered, revealing a framework of black pixels, the skeletal structure of the digital world. Ailin tore at the pixelated fabric as if it were mere paper, exposing the black grid beneath. Stepping through the tear, he entered the digital realm.

Mosaic patterns flipped and turned around him, and soon, Ailin found himself within a sealed, black space. Before him stood enormous, wolf-like creatures, ripped straight from the digital landscape.

"Roar..." one of the beasts howled, leaping at him with bared fangs.

"Hadō #4: Byakurai!"

A bolt of lightning pierced the creature, dispersing it into a shower of pixels. It was merely the beginning. As Ailin progressed, more and more digital entities materialized, attempting to impede his advance.

"How troublesome..." Ailin sighed, observing the endless horde.

Though they were weak, their sheer number was grating. It was like trying to crush ants underfoot – even if you squashed most of them, the few that remained would leave you feeling uneasy.

Boom!

A surge of reiatsu exploded from Ailin, its sheer force overwhelming the digital creatures, reducing them to scattered pixels. The very fabric of the game space strained under the pressure, ultimately succumbing.

Bang!

Yukio's Fullbring, "Invaders Must Die," was indeed impressive. However, its limitations were clear – it couldn't confine anyone with significantly greater reiatsu than its user.

Ailin had initially entered willingly, and neither Ginjo nor Tsukishima had exerted their reiatsu within the space. But now, having grown tired of battling the digital horde, Ailin had unleashed his power, shattering the fragile digital world.

Fortunately, Yukio's delay had bought enough time for Tsukishima to wake Ginjo.

...

Observing the wound on Ginjo's left arm, Ailin raised an eyebrow. "What's this? Still clinging to naive hopes? Or do you believe adding these three to your side makes you a match for me?"

Ginjo's eyes flashed with resentment at Ailin's mocking tone. He ripped the cross-shaped necklace from his neck and placed it onto the hilt of his Zanpakuto.

Boom!

Black reiatsu surged as Ginjo fused his Fullbring with his Zanpakuto, causing his spiritual pressure to escalate to a higher level.

"Oh? Aside from Shinigami powers, you've mastered another force, I see."

Ailin had known Ginjo possessed Fullbring since he saw him with the other Fullbringers. But he wasn't sure if Ginjo had only mastered the necklace or if he had also incorporated the Substitute Shinigami Badge.

"Is this your trump card? Do you believe this slight increase in reiatsu is enough to make a difference?"

"Of course not," Ginjo grinned, his teeth bared. "Teacher Ailin, though you never taught me, I ultimately mastered that power..."

"Behold—"

"Second Stage Bankai!"

Ginjo's reiatsu exploded, multiplying several times over, its force distorting the clouds above. As his spiritual pressure stabilized, white bone-like armor appeared on his shihakushō, and two pairs of red, dragonfly-like wings sprouted from his back.

Ailin stared at Ginjo's transformation, silent.

Achieving a second Bankai on top of the first? A second stage Bankai?

No, it was simply Ginjo's misconception. This form's power boost was similar to Bankai, so he mistakenly labeled it as such.

In reality, this wasn't "Bankai," but "Hollowfication."

"I never expected you to master even this power... Ginjo, I take back what I said earlier. You're no less impressive than my other three disciples. To have reached this level without my guidance, your talent is truly second to none."

"Hmm?"

Initially pleased by Ailin's praise, Ginjo's smile faltered at the last statement. He had displayed such power, yet in Ailin's eyes, he was only second best?

"Perhaps your current form can truly surprise me. Come, Ginjo. Show me what you can do in this state!"

Swoosh!

With a beat of his wings, Ginjo broke the sound barrier, charging towards Ailin with his red Zanpakuto raised high. He slashed at his target.

Clang!

Finally, under Ginjo's assault, Ailin drew his own Zanpakuto.

The clash of their swords created a shockwave that demolished Yukio's mansion, leaving a vast crater in its place. Thankfully, the secluded location prevented any casualties.

Even Tsukishima, Yukio, and Giriko remained unharmed. As the shockwave approached them, Tsukishima plunged his sword into the ground, creating a deep pit that shielded them from the blast.

Clang, clang, clang...

Sparks flew as Cross of Scaffold and Ailin's Zanpakuto locked in a fierce struggle. But despite Ginjo's relentless pressure, Ailin remained unmoved with his sword held effortlessly in one hand.

"Drink!"

Seeing that he couldn't gain any advantage in strength, Ginjo gave up grappling with Ailin and swung his Zanpakuto wildly at him.

Clang! Clang!

Boosted by his powerful spiritual pressure, Ginjo's attacks were forceful and heavy, and the shockwaves from each attack caused destruction in the surroundings.

Unfortunately, no matter how ferocious his attacks were, he couldn't make Ailin budge an inch.

"Hah!"

Realizing he couldn't overpower Ailin, Ginjo broke away and soared into the air, pointing his Zanpakuto at his former teacher. Red reiatsu converged at the tip, forming a sphere that launched towards Ailin.

Cero – a technique only Gillian-class Hollows and above possessed. It seemed that Ginjo's Hollow powers had increased to such an extent, granting him access to this devastating attack.

Boom!

Cero was the ultimate attack of a Hollow, its power directly proportional to the user's reiatsu. The red beam of energy, dimming the sky with its intensity, hurtled towards Ailin.

Ailin raised his Zanpakuto to deflect the Cero, but suddenly, the ground beneath him crumbled, and a slender blade pierced through his foot.

"Oh?"

Ailin raised an eyebrow, and his reiatsu exploded around his foot.

Boom!

The ground exploded, sending flames shooting skyward. Tsukishima, who had attacked from below, was flung back, his body splattered with blood as he was enveloped by black pixels. The blade that had pierced Ailin's foot was pulled back into Yukio's game space. Strangely, Ailin's foot remained unharmed.

Ailin understood why. Tsukishima's attack wasn't meant to injure him but to insert his "existence" into Ailin's past, turning him into a "friend."

Distracted by Tsukishima, Ailin didn't have time to block the Cero, and it struck him directly.

Boom!

A massive explosion erupted, sending a mushroom cloud billowing into the sky. Yukio's mansion and the surrounding hillside were utterly annihilated.

Tap, tap, tap...

A figure shrouded in white reiatsu emerged from the flames – Ailin, unscathed.

Though Hollowfied Ginjo was undoubtedly powerful, surpassing most captain-level Shinigami, a single Cero was far from enough to injure Ailin.

"Clever, they've already escaped."

As Ailin walked out of the wreckage, he could no longer sense Ginjo or the others.