(Quite a few revisions; earlier parts may contradict themselves.)
Soul Society, West Seirei Gate — the Hakudōmon.
A handsome youth in a white yukata stared at the cloud-piercing wall of sekki-seki that split Seireitei from Rukongai. Beside him loomed a giant holding a seven-shaped pair of axes.
"Halt. Present your gate-pass if you wish to enter Seireitei."
The giant's voice boomed from above as the boy sized up the ten-meter titan.
"I am Jidanbō, guardian of this gate. No pass, no entry."
Jidanbō paused, eyeing the youth at his feet with a mischievous glint.
"Of course, you could try to knock me down and force your way through."
Glancing at the eager giant tightening his grip on the axes, then at the plain blade at his own waist, the boy hesitated, pulled a card from his robe, and—realizing he barely reached the giant's knee—flung it upward.
"Let's see… Jie Chengxian, from West-80, reason for entry… new student at the Shino Academy."
Jidanbō stared in surprise; it had been ages since a soul from the lawless 80th District won entry to Seireitei. Yet he said nothing. Hoisting the Hakudōmon with his massive back, he waved the boy through.
"Off you go."
With a quick thanks, Jie stepped past the gate into the heart of Soul Society—Seireitei.
Glancing at the address on his leaflet, he felt a tangle of emotions.
[Six months ago I was an ordinary Earthling; now I'm in Soul Society enrolling in Death-God school…]
[And the one who dragged me here was the Soul King himself.]
This was no ordinary transmigration—he had been personally scooped up by the Soul King.
According to the King's lingering will, the balance among Soul Society, Hueco Mundo, and the World of the Living still held, but the future's "variables" had grown too few; the world was a straight line converging to one end.
Not wanting everything to march toward a set conclusion, the King had hauled Jie from among countless worlds and planted a "Hōgyoku-like" seed deep in his soul.
Similar, yes—yet more a "controllable miracle."
It sensed the desires and patterns of nearby souls, guiding reiatsu to evolve as needed, but for now it slumbered, waiting for Jie's own power and will to hatch it.
All Jie had heard was "Hōgyoku-like," with no clue what the cheat actually did.
Other travelers at least got grand rituals; he'd skipped the process entirely. Same face, but was this reincarnation or body-swap?
He didn't even know the timeline. Blame Kubo for writing cryptic poems instead of dates—no wonder fans say the guy just draws manga; what does he know about Bleach?
Musing, he reached the Shino Academy in minutes. Today was freshman orientation, and the streets bustled with hopefuls. The only school that minted shinigami, it promised graduates a cushy, decadent life.
As he queued, a daydream flared: some snobby noble snarls that a mud-foot doesn't belong, swings at him, and is felled by a casual flick. Teachers gasp, report to the captains and old man Yamamoto, and the Gotei 13 scramble to recruit him.
Which captain would he pick when they fought over him? Sigh—genius is troublesome.
"Excuse me, you must be Jie Chengxian, sponsored by Lieutenant Ōmaeda Shinozuke of the Second Division. This way, please."
The receptionist shattered his fantasy. Right—Ōmaeda's father had spotted him on a mission to the 80th, tagged him as a prospect, and brought the find to Yamamoto. The old man had trekked out, taken him as a personal disciple—he was half nobility now!
Besides, guards were everywhere; such crass scenes only happened in novels. Reading too many power-trip stories had poisoned his expectations.
Following the upperclassman inside, he found tiered desks and a blackboard—just like university. Familiar surroundings tugged his eyelids downward.
"Sorry, excuse me."
A low, resonant voice snapped him awake; he stood to let the newcomer pass.
"No problem—old habit; classrooms make me drowsy."
The stranger nodded politely and sat to his left. Brown hair, black-framed glasses, an air of calm intelligence—vaguely familiar, yet he couldn't place him.
"Hello. Aizen Sōsuke. Pleased to meet you."
Catching Jie's stare, the man smiled and offered a hand.
"Jie Chengxian. Likewise…"
Embarrassed at being caught, Jie shook hands—until the name hit him.
Aizen Sōsuke, future Fifth-Division captain, Soul Society's greatest traitor, emperor of Hueco Mundo—sitting right beside him? Suddenly, staying awake in class was guaranteed.
"Oh?" Aizen gently withdrew his slightly crushed hand, pushing up his glasses. "This is our first meeting, yet my name surprises you, Jie-kun."
"Could you tell me why?"
His voice invited trust—if you didn't know better.
"Uh, you share a name with a friend I had back in the living world. Mistook you for him."
Jie shrugged it off. Every soul kept memories of life; the excuse held. And with his own cheat, why fear Aizen?
Heh—why not make Aizen submit now, before the Hōgyoku ever exists?
"I see." Aizen smiled, disbelieving but amused. "Then fate seems to have paired us."
He could read lies in posture and breath; he knew Jie's shock had come from matching the name to the face.
So much for a quiet life at the academy.
Yet Aizen had no idea that inside this boy from the 80th slumbered the Soul King's personal "variable."
From this instant, the world's track had already shifted.