One Piece: Kaido's adopted son, starts with the Eight Gates Formation.

Whitebeard walked behind, his naginata slung over his shoulder. Akainu followed closely behind, looking annoyed, the magma on his body providing the only light in the darkness. Kenpachi Zaraki brought up the rear, his eyes glowing in the darkness, a grin on his face, looking at everything as if searching for an opponent.

Shanks followed, appearing silently in the middle of the group; even Kaido didn't notice when he arrived.

One floor. Two floors. Three floors.

Each layer of the barrier was opened by Hyosube Ichibei drawing circles with a lollipop. By the fourth layer, Kaido finally couldn't hold back any longer.

"Monk, why are the circles you drew with the lollipop getting more and more crooked?"

"You try drawing one," Hyosube Ichibei replied expressionlessly.

"ha?"

"This lollipop gets thinner and thinner the more you lick it, the harder it is to hold."

Kaido glanced at the lollipop—indeed, after just one lick and repeated use, the lollipop, which was originally thicker than his arm, had shrunk considerably.

"Why are you licking it!" Kaido roared.

"Your young master asked me to have a taste," said Hyosube Ichibei calmly.

"Then you shouldn't—never mind, never mind." Kaido dropped the subject.

Fifth floor. Sixth floor. Seventh floor.

The deeper they went, the heavier the oppressive feeling became. By the seventh floor, even the white-bearded man frowned slightly.

"There's something very off about this place," the white-bearded man said in a low voice. "It's like something's alive inside the walls."

"That's the resentment of sinners sealed in the deepest hell throughout the ages," Hyosube Ichibei said without turning his head. "The malice accumulated over hundreds of thousands of years has seeped into every single stone."

"That sounds disgusting," Akainu muttered.

"Resentment?" Kenpachi Zaraki's eyes lit up. "Can we fight him?"

"No," Hyosube Ichibei and Akainu said in unison.

The eighth layer of the barrier—the final layer.

The barrier on this level is completely different from the previous ones. There are no demonic inscriptions, no spiritual pressure fluctuations, only a simple stone door. The stone door has no lock, no seal, only a single word engraved on it.

"none".

Hyosube Ichibei stopped in front of the stone gate and glanced back at Lynn.

"Beyond this door lies Aizen Sousuke's cell." He paused. "I'll say it one last time—he's dangerous. Not physically, but mentally. Every word he speaks is purposeful, every glance he gives is calculated. He'll use what you care about most to manipulate you."

Lynn took the lollipop out of his mouth, looked at Hyosube Ichibei, and tilted his head.

"I know everything you're saying."

"Then you should—"

"No matter how capable he is, he's still a locked-up person," Lynn said. "What's there to be afraid of in a locked-up person?"

Hyosube Ichibei opened his mouth, but ultimately said nothing.

He held up the lollipop and drew one last circle on the stone gate.

The stone door slid open silently.

A pure white space appeared before everyone. No walls, no ceiling, no floor—or rather, everywhere was walls, everywhere was ceilings, everywhere was floor. White. Pure white. Infinitely extending white.

In the very center of this white expanse, there is a chair.

No, it's a sealing device. A black chair, covered in demonic runes. A person sits in the chair, their entire body bound by black ribbons, only their face visible.

A smile was on his face.

That smile he's had since the day he was sealed away.

Gentle. Composed. Someone you'd want to keep at least 300 meters away from.

"Oh." Aizen Sousuke slowly opened his eyes, his gaze passing over Hyosube Ichibei, over Kaido, over Whitebeard and Akainu, and finally landing precisely on the small figure floating in mid-air.

"You've arrived."

Aizen's voice echoed in the empty space, neither too loud nor too soft, neither too warm nor too cold.

"Hmm." Lynn floated closer and looked Aizen up and down.

"It's smaller than I expected," Aizen said, "but quieter than I expected—how should I put it—."