Just as Ukitake and his squad stepped out into the courtyard to deploy, Kaien returned to the barracks, carrying Miyako's limp body in his arms.
"Kaien, is she alright?" Rukia asked, rushing forward.
"She isn't in immediate danger, but she has fallen into a deep coma," Kaien replied, shaking his head as he held his wife close.
Hearing the news, a collective breath of relief washed over the assembled squad.
Kaien carefully carried Miyako into the medical ward to rest, assigning a junior medic to watch her vitals.
However, just as Ukitake and Kaien stepped out into the hall to discuss the ambush, a blood-chilling scream erupted from the ward.
Rushing back into the room, they found the medic collapsed on the floor, his face frozen in terror as one stiff finger pointed toward the bed.
Sitting upright, Miyako was emitting a dark, suffocating Spiritual Pressure, her eyes blank as a sinister shadow seemed to devour her from the inside out.
"What is happening to her?" Rukia gasped in horror.
Ukitake's brow furrowed, his hand resting on his Zanpakutō.
"This malicious Reiatsu… is it Hollowfication?"
While the commanding officers stood frozen in shock, the possessed Miyako suddenly move, striking down two more medics who tried to subdue her.
Shoving past the falling bodies, Kaien frantically rushed forward and grabbed his wife, pulling her into a desperate embrace.
"Miyako, snap out of it! What's wrong with you?"
Her face twisted into a ferocious, unnatural sneer.
Then she brutally broke free from Kaien's grip, used Shunpo, and blurred through the open window, disappearing into the night.
Recovering from the blow, Kaien was the first to vault out the window in pursuit, with Ukitake and Rukia following closely behind.
"Miyako!" Kaien shouted as he tore through the dense forest, receiving no answer but the rustling of leaves.
Pushing through the brush, Kaien suddenly stopped in a moonlit clearing, his breath catching in his throat as he spotted fragments of Miyako's torn Shihakushō and her abandoned Zanpakutō lying in the dirt, surrounded by the overwhelming stench of a Hollow.
As Ukitake and Rukia broke through the treeline to catch up, the monstrous entity hiding in the shadows stepped into the moonlight.
It was a grotesque, crawling Hollow, its head covered in fleshy tentacles and its body armed with six jagged limbs.
The bone mask on its face had hollow, empty eye sockets.
Staring at the monster standing over his wife's shredded clothes, Kaien drew his blade.
"You bastard… how many Shinigami have you devoured?"
It was a rhetorical threat born of grief, but to their horror, the Hollow actually answered.
"Apologies," the beast rasped, its voice echoing from behind the bone mask. "I don't bother keeping track of my meals."
Ukitake tightened his grip on his dual blades, taken aback by the terrifying reality of an ordinary-looking Hollow possessing clear sapience and speech.
"You will regret crossing me," Kaien growled, leveling his blade.
"Regret?" the Hollow laughed, its tentacles writhing. "Why should I, Metastacia, feel regret? The only pity is that I didn't make better use of that little female Shinigami's body before I discarded it!"
Hearing the monster mock his wife's death, Kaien's heart burned with explosive rage.
His Spiritual Pressure flared violently as he roared, "You deserve to die!"
Stepping forward, Rukia reached for her Zanpakutō to support her senior officer, but Kaien threw his arm out to block her path.
Then he turned his head to look at Ukitake, his gaze hardening with unwavering resolve.
"Captain, please allow me to handle this alone. For my honor, and for Miyako's, I must slay this beast with my own hands."
Understanding the crushing weight of Kaien's grief and trusting his Vice-Captain's combat prowess, Ukitake offered a solemn nod before stepping back, allowing Kaien to seek his vengeance.
Kaien unleashed his Spiritual Pressure and charged toward Metastacia like a bolt of lightning.
His eyes burned with fury, and the unreleased Zanpakutō in his hand gleamed with cold intent.
Although Metastacia possessed human-like intelligence, its combat strength was only barely scraping the Vice-Captain tier.
Faced with Kaien's enraged, blistering speed, the Hollow was caught entirely off guard.
With a brutal swing of his blade, Kaien instantly severed two of its jagged hands.
The Hollow roared in agony, but Kaien gave it no chance to recover.
Using Shunpo, he vanished and reappeared directly in front of the beast, reaching out with his free hand to tightly grasp the fleshy tentacles writhing on Metastacia's head.
The creature struggled desperately, but Kaien's physical strength far surpassed its own.
"Let the waters rage and reverse! Nejibana!"
Kaien roared the release command, unleashing the full power of his Zanpakutō.
In an instant, the humid air around them seemed to freeze, and a massive wave of crashing Spiritual Pressure spread through the clearing.
As the command faded, the steel in his hand transformed into a massive trident shimmering with a deep blue, aquatic glow.
Then, suddenly, Metastacia stopped struggling.
Staring at the Shinigami with its hollow eyes, the beast offered a baffling, mocking remark.
"You may be strong… but you touched my tentacles."
In that exact moment, the massive trident in Kaien's hand vanished.
It simply evaporated into thin air, leaving only a crumbling hilt behind.
"Kekekeke…" Metastacia let out a sickening laugh. "Shinigami, you fell right into my trap. Anyone who physically touches my tentacles will have their weapon instantly destroyed!"
With that, the Hollow whipped its remaining tentacles forward and violently knocked the unarmed Kaien across the clearing.
Seeing the situation instantly turn dire, Rukia drew her sword and prepared to rush into the battle, but Ukitake threw an arm out to stop her.
"Rukia, stand down. This is Kaien's fight," Ukitake ordered, his tone heavy but firm. "If you intervene now, where would his dignity lie? Where would the dignity of his fallen wife lie? Watch calmly."
Rukia's face twisted with desperate anxiety.
"But Captain, his Zanpakutō is gone! Facing a Hollow barehanded is suicide!"
"Rukia, you must understand that there are two kinds of battles in this world," Ukitake explained softly, his eyes fixed on his Vice-Captain.
"A battle fought for one's life, and a battle fought for one's pride. Kaien is fighting for his pride! If you help him, you may save his life, but what about his soul?"
Kaien steadied himself in the dirt, his gaze locked firmly on the Hollow.
"Even without my Zanpakutō, I will tear you apart!"
Clenching his fists, an intense aura of raw Hakuda flared from his entire body.
Metastacia lunged again.
Kaien smoothly sidestepped the attack, pivoting into a devastating kick that struck its abdomen.
However, the crushing blow did surprisingly little against the beast's thick hide, and Metastacia quickly retaliated, lashing out with its razor-sharp tentacles.
The two engaged in a brutal hand-to-hand brawl, with Kaien relying entirely on his masterful Hakuda to hold his ground against the Hollow's superior reach.
Despite being at a massive disadvantage, he still managed to forcefully tear away several of the beast's tentacles with his bare hands.
As they momentarily separated, Metastacia quietly observed the bleeding Shinigami, a mocking smile curling at the edge of its bone mask.
"It seems your Captain and your little friend won't be coming to your aid."
Panting heavily, Kaien wiped the blood from his mouth, his eyes resolute.
"I don't need them! I am more than enough to slay you!"
"Kekekeke…" Metastacia let out a strange, wet laugh. "Then I'll let you follow in your wife's footsteps. After I take over your body, I'll use your face to kill your precious companions and devour them."
With that, Metastacia's central mass of tentacles shot toward Kaien like lightning.
Kaien instinctively raised his arm to block the strike, but the fleshy appendages pierced through his defense and drove straight into his chest.
Instantly, Kaien froze in place, motionless as if he had been turned to stone.
The pure blue Spiritual Pressure radiating from him gradually darkened, swallowed by a suffocating black aura.
As Metastacia forced its way into Kaien's body, the Hollow's original outer shell shattered into ash, revealing that the parasitic tentacles had been its true body all along.
The sudden, horrifying turn of events left Ukitake and Rukia unable to react in time.
They could only watch helplessly as Kaien was fused with the Hollow.
"Kaien…" Rukia whispered, her voice trembling in terror.
Slowly raising Kaien's head, the possessed Vice-Captain smirked, his voice distorting with a perverse echo.
"Little girl, were you calling me?"
"Kaien!" Rukia screamed, desperately trying to awaken her senior officer's buried consciousness.
"You care so much about this guy, so let me devour you next!"
Metastacia hissed and forced Kaien's body to charge directly toward Rukia.
Drawing his dual blades, Ukitake immediately stepped forward to block the attack.
"Rukia, get back now!"
The Captain's roar snapped Rukia out of her dazed panic, prompting her to frantically retreat from the center of the battlefield.
After exchanging a few heavy blows with Ukitake, Metastacia realized the Captain was deliberately holding back, having no intention of striking a lethal blow against his own subordinate's body.
"You're trying to figure out how to safely separate me from this guy, aren't you?" Metastacia taunted, parrying Ukitake's strike.
"I exist as a parasitic spirit body, and so does he. There is absolutely no way you can pull us apart without killing him."
Hearing the cruel reality, Ukitake's eyes hardened, forcing him to immediately change his tactics.
Since he could not save Kaien, he had no choice but to slay him alongside the Hollow to protect the Seireitei.
Shifting into a lethal stance, Ukitake struck Kaien's shoulder with a brutal slash, forcing Metastacia to retreat.
Accessing Kaien's stolen memories, the Hollow realized that this sickly Shinigami was a Captain-level powerhouse, a monster far beyond its own capabilities.
Knowing it could not win a battle of attrition, Metastacia decided it needed to escape.
Just as Ukitake prepared to launch a finishing strike, a violent tremor surged through his frail lungs.
He dropped to his knees, coughing harshly as his grip tightened around his Zanpakutō.
'Damn it. Why did my illness have to flare up now of all times?'