No… it still couldn't be achieved.
Kurotsuki Renya sat cross-legged on the cold stone floor, Tenrei-maru resting horizontally across his knees, his expression tight with frustration. He exhaled slowly, forcing his reiatsu to settle. He had attempted for years, yet the final step continued to elude him.
He could not realize Tenrei-maru's true form.
He could not materialize the spirit.
And without materialization, Bankai—Daikai, the "Swastika"—could never be mastered.
The process for Shikai and Bankai were vastly different. Shikai required attunement and communication: reaching one's inner world, learning the Zanpakutō's name, forging synchronization through dialogue and acceptance. Bankai, however, required full manifestation—forcing the Zanpakutō spirit into the physical world and subjugating it through strength or recognition.
Renya had attempted this countless times.
Nothing.
"Are you sure you don't want to use the Kishin Shintai?"
Yoruichi's voice echoed lightly through the cavern training hall. She stood beside him, holding the humanoid wooden device in her hands—the same forbidden tool the Onmitsukidō once used.
"If you use the God-Transforming Body, your Zanpakutō will manifest instantly. You could force a breakthrough."
Renya let out a dry laugh. "Or I could get myself killed."
He knew exactly what the Kishin Shintai was. One of the most dangerous restricted tools created by the Shihōin family, capable of forcibly dragging a Zanpakutō spirit into the physical realm. Ichigo Kurosaki had once used it—though in his case, Zangetsu's manifestation had been tied to his mixed Quincy and Shinigami heritage, not a normal Zanpakutō.
The tool's power was brutal. If the wielder could not subdue their spirit, death was the only outcome.
"I'm not like Ichigo," Renya admitted quietly. "Ichigo had already achieved partial materialization long before the training. Even Abarai Renji manifested Zabimaru before his first imperfect Bankai. But me… I haven't even materialized Tenrei-maru once."
"If I force it… I might not survive the first strike."
"Stop overthinking."
Yoruichi clapped him on the shoulder, grinning. "Come on. The hot spring is finally ready. You need rest before you burn yourself out."
"The underground spring? You really finished it?" Renya blinked.
They'd accidentally discovered it during a sparring match—Yoruichi had smashed him through the floor, revealing the natural water source. He hadn't expected her to turn it into a proper hot spring so quickly.
"It's ready. And the schedule says today is available."
Yoruichi winked. "Which means you're coming."
Renya's face brightened despite himself. He hurried off to grab a towel, sprinting to the room built into the far corner of the underground hall. Steam poured out as he slid the side-door open. Heat washed over him immediately.
Stripping quickly, he slipped into the water with a sharp splash.
"So hot…"
The springs ran at about forty-three degrees—high, but perfect for relaxation and spiritual pressure recovery.
He let himself sink deeper—
—when the door slid open again.
"Move over. I'm bathing too."
"Y-Yoruichi-senpai!? You're— you're coming in!?"
"Of course I am. I've been training you nonstop; I deserve this more than you."
Without hesitation, she began undressing. Renya whipped his head away, face burning.
With a soft splash, Yoruichi sank into the water beside him.
"What's wrong? Don't forget you aren't even an adult yet."
He stiffened. "Still… you're a woman…"
"In Soul Society, you're only fifty-eight," she teased. "You won't hit adulthood until you're a century old."
Before Renya could protest, more voices echoed from outside.
"It's finally finished! We can bathe today, right?"
"Obviously! As if we'd let the guys get it first!"
Yadomaru Lisa and Kunanbō Hiyori slid the door open.
"Huh? Renya? Why are you here?" Lisa asked.
"Oi! Today is girl-only time! Why's a brat soaking in here!?" Hiyori barked, hands already on her clothes.
Renya panicked. "Yoruichi-senpai said I could use it today!"
Yoruichi lifted a lazy hand. "He's still a kid. Doesn't count."
Lisa shrugged. "He's not technically an adult… let him stay."
Before Renya could argue—
Hiyori had already stripped and cannonballed into the pool, sending a wave splashing over everyone.
Lisa followed, slipping into the water beside Renya.
He stared down into the water, face burning red.
"The water's too clear…"
He whispered, mortified.
The spring was crystal-clear, with small stones lining the bottom. And although the water level covered everything below the chest…
His imagination betrayed him.
A sudden nosebleed erupted from Renya's nostrils.
"HAH! Look at him! He's bleeding out his damn face!" Yoruichi cackled.
Renya frantically healed himself with Kaidō, sinking lower into the water in embarrassment.
Lisa's voice softened. "Renya… you've seemed frustrated recently. Restless. Like you're in pain."
He froze.
"Is it that obvious…?"
Yoruichi nodded.
"You're pushing too hard. You've been obsessed with Bankai every single day."
Hiyori popped her head up from the water. "Even Hiyori noticed, dumbass."
Renya exhaled shakily. "Without Bankai… I can't defeat Aizen."
He could fight Aizen now. He could pressure him.
But defeating him?
That was impossible.
"Rushing won't help," Yoruichi said gently. "You still have time. Don't break yourself before the battle even starts."
Renya nodded, but his stomach twisted with the same familiar dread.
Time was not abundant.
Only two years remained before the main events of the story began.
Two years before Aizen moved.
Two years before Renya had to return to Seireitei.
If he still lacked Bankai by then…
He would have no choice but to use the Kishin Shintai.
Dangerous or not.
He would risk everything.