Over fifty years ago, a major incident shook the Soul Society.
The aftermath led to the disappearance of four Gotei 13 captains, three lieutenants, and a vice-chief of the Kidō Corps. Two captains and a Grand Kidō Chief defected.
It was one of the most damaging events to ever strike the Seireitei's core vitality in over a millennium.
Most records of the incident were sealed away as classified. Few current Gotei 13 members knew the full truth.
When it came to cats in the world of the Shinigami, it was impossible for Tachikawa Shin not to think of one person.
Shihōin Yoruichi.
Former Captain of Squad 2—one of the two captains who had defected.
Shin recalled that Shihōin Yoruichi had known Shiba Kūkaku for a long time. They'd once been close friends.
But fifty years ago, Kaien would've just been graduating from the Shin'ō Academy. Kūkaku would've been a little girl. At that time, Yoruichi was already leading the Onmitsukidō and commanding Squad 2. For them to have had a deep bond already? It didn't quite add up.
And strangely, the Central 46 had never convicted Yoruichi of any crime. The only one labeled a criminal had been Urahara Kisuke, and only he had been denied access through the Senkaimon.
Shin kept his gaze on the black cat, watching it until it lapped the last of the drink, then leapt from the table and vanished with swift, silent steps.
The reception wound down. Guests trickled away.
Spotting Ganju, Shin waved him over.
"Shin-aniki?" Ganju jogged up.
"Where's your sister?" Shin asked casually.
Ganju looked around. He'd been too busy helping guests to notice. "No idea. You need something?"
"Not really…" Shin paused, then added, "Hey, do you guys keep a cat? I saw one drinking from a cup earlier."
Ganju blinked. "We don't, but—oh! Right, my sister sometimes carries around this stray she picked up. No idea where it came from. If you saw a cat today, that was probably it."
As he spoke, Shin spotted Shiba Kūkaku emerging from the house—cradling that very same black cat in her arms.
That confirmed most of his suspicions.
"Hey, Sis!" Ganju called out.
Kūkaku turned her head at the sound and walked toward them, the cat still lounging lazily in her arms.
"Shin-aniki says he needs something," Ganju said.
Kūkaku looked at Shin, puzzled.
Shin just smiled. "It's nothing. Kūkaku-san, you look really beautiful today. You should dress like that more often."
She shot him a sideways glance. "I'll wear what I like, when I like."
Shin's eyes drifted to the cat in her arms. Its golden eyes stared right back at him.
"Is that your cat?" he asked.
Ganju reached out to pet it—and got clawed.
"Ow! It scratched me!"
Kūkaku didn't respond to her brother's whining. "Sort of," she said.
"I saw it drinking from a cup on the table earlier. Pretty smart," Shin noted. Despite being so close, he didn't try to probe its reiatsu again—last time, it had clearly sensed the attempt.
Kūkaku gently petted the cat's head. It purred and sank deeper into her arms, basking in her touch.
"It is smart," she said.
"What's its name?"
She hesitated. "…Hasn't got one yet."
Then, eyeing Shin, she asked, "You like cats?"
Shin nodded.
She thought for a moment, then suddenly extended the cat toward him.
He hadn't expected her to just hand it over. He reached out, only for the cat to swipe a claw at him in a blur of motion.
He barely dodged.
Kūkaku laughed. "Looks like it doesn't like you."
Shin: "…"
Ganju grumbled, "That thing's too mean. Why are you even keeping it, Sis? Just toss it."
The moment the words left his mouth, the cat gave a sharp "meow," then pounced onto Ganju's face and scratched it up with ruthless precision.
"AAAHH!"
Ganju screamed and collapsed to the ground.
The racket drew attention. Shiba Miyako came over, brow furrowed, asking what happened.
Ganju, teary-eyed, cheeks clawed raw, wailed, "Sister-in-law, her cat attacked me!"
And yet—Miyako, with a calm smile, took the cat from Kūkaku's arms without a hitch, stroking its fur gently. The cat relaxed in her arms, purring like it was in paradise.
Shin watched, thoughtful. Clearly, getting close to this feline wasn't going to be so simple.
Abandoning the idea for now, he said his farewells to Kaien and quietly took his leave.
Later that evening, Kūkaku returned to her room with the black cat nestled in her arms.
It leapt up onto her bed in one smooth motion, curling lazily atop the blankets.
Kūkaku began stripping off her kimono. She couldn't stand wearing such formal stuff for long.
Then—
"Who was that guy just now?"
The voice came from the bed.
The cat had spoken—a deep, distinctly male voice.
"…Who?" Kūkaku blinked, caught off guard.
"The one you called Tachikawa. He's Third Seat of Squad 4, right? Tachikawa Shin. Looks like he gets along with your brother."
Kūkaku raised an eyebrow. "What about him?"
"Does he stand out in any way?"
"What kind of question is that?" she asked, confused. "He's pretty well-known from his time in the Academy. Started a student council, graduated straight into Third Seat. I heard he beat Gin Ichimaru during that last inter-squad tournament—even when Ichimaru had Bankai."
The cat's golden eyes remained unblinking. Its tail swayed slowly from side to side.
"…Why are you suddenly asking about him?" Kūkaku pulled on a shirt, brushing out her hair.
The cat murmured, "The way he looked at me the first time... it was strange."
"He said he liked cats, didn't he? Maybe he just—"
"No," the cat cut in. "He was surprised. And it wasn't the look someone gives a cat. It was the look of someone who recognized me."
Kūkaku froze, shocked. "You mean… he knows who you really are?!"
The cat was silent for a long time.
"Probably not… I'm not sure. But later, he did something dangerous."
"What?"
"He used reiatsu detection on me. Tried to trace my spiritual signature."
Reiryoku threads—visible only to high-ranking Shinigami—appeared like floating ribbons of energy. Shinigami had red threads. Humans, white. They were used for scouting and spiritual identification.
No ordinary Death God would bother using that technique on a cat.
The cat's golden pupils flickered.
And Kūkaku, realizing the implications, grew visibly tense.