Compared to her older sister, Kotetsu Kiyone was cheerful, outgoing, and often rambunctious.
Thanks to the fact that her sister was the Fourth Division's vice-captain, she came and went from the squad barracks freely, with few restrictions.
Like Isane, Kiyone didn't live in the squad barracks but had her own home within Seireitei. With nothing urgent on her plate after the exchange event, she had left the Thirteenth Division early and headed to the Fourth, intending to walk home together with her sister.
What she didn't expect was to open the door and stumble upon a scene that stunned her.
Her sister was in Tachikawa Shin's arms. Hugging. Closely.
"You… you two…"
Kiyone stood frozen, unable to form full words. Then, realizing what she was looking at, she quickly backed out of the office and closed the door behind her with a sharp click.
"Sorry!!"
Isane, who had already been flustered by Shin's heartfelt confession, felt her mind go completely blank after getting caught in the act.
She hurriedly pushed Shin away and stood awkwardly in place, hands clenched at her sides, her face burning a vivid red that practically glowed.
Shin let out an inward sigh. A glance at his system panel showed her favorability score fluctuating nervously up and down.
What a shame.
He'd been hoping to ride the momentum and push things further. But now, that was clearly off the table.
"Well then… I'll be going, Yūne-neesan."
Isane didn't respond. Her head was lowered so far she could have vanished into the floor.
As Shin stepped out of the office, he found Kiyone standing there in the hallway, her bright eyes blinking rapidly at him, lips curved in a knowing, mischievous smile.
She was small—even more petite than Rukia—and dressed like a boy: short-cropped hair, sharp posture, and a plucky presence.
Despite her appearance, she was actually older than Shin by a good margin.
To her, if Tachikawa Shin and her sister ended up together, it would be a good thing. First, Shin was exceptional. Second, her sister had been alone for far too long—having a partner wouldn't hurt.
Once Shin was gone, Kiyone gently pushed the door open and stepped into the office.
Isane's face was still flushed, though she had managed to compose herself somewhat and was now seated at her desk.
"…Why are you here?" she asked, voice soft.
"Looks like I came at the wrong time," Kiyone grinned as she sauntered in. "Sorry for interrupting your moment, Sis."
"Don't say nonsense!" Isane snapped. "We're not like that!"
But the blush on her cheeks made her denial utterly unconvincing.
Kiyone flopped down in front of her sister, eyes gleaming with curiosity. "Come on, when did it start? How far have you two gone? Kissed yet? Did you… you know? Are you two gonna live together?"
The flood of questions made Isane's head spin. She waved her off frantically. "I told you we're not in that kind of relationship! Stop imagining things!"
Kiyone gave her a long, skeptical look.
Isane pursed her lips, then murmured softly, "…Not yet."
After all, this was her little sister—there were few secrets between them.
She was at least thankful it was Kiyone who walked in on them, and not someone else.
Kiyone finally smiled again. "So was that a confession just now? Who made the move?"
Isane went quiet again.
Kiyone leaned forward, poking. "Sis!"
"…He did…"
"And you said yes?"
"…No…"
"Sis!!" Kiyone groaned. Then realization dawned. "Oh no—I really did walk in at the worst time! Damn it, I ruined it!"
Isane shook her head, still dazed. "…I haven't made up my mind yet."
"Haven't decided?" Kiyone tilted her head. "So you don't like him?"
"…"
Kiyone could read her sister like a book. The flustered, evasive expression said more than any words.
"You do like him!" she declared triumphantly.
"…I don't know how to explain it," Isane whispered. "I just always thought of him as a younger brother… or a junior."
Kiyone nodded thoughtfully. "Well, yeah, he only just graduated from Shin'ō Academy, right? He can't be that old… Hmm…"
She turned her head slightly. "Sis, how old is he exactly?"
Isane thought for a moment. "Not even twenty, I think."
She'd seen it in his records.
Kiyone's eyes went wide. "That young?!"
In the Soul Society, where Shinigami lived for centuries, age was usually measured in decades—or centuries. Someone like Shin, not even twenty yet, was practically a baby.
"So… is that what's bothering you? That he's too young?"
Isane hesitated… then slowly shook her head.
Kiyone tilted her head, thinking. "Still, he doesn't act young at all. And he's strong as hell…"
Her eyes glinted. "Sis, I think you should stop overthinking it. Just say yes. From what I see, you're the one getting the better end of the deal!"
That hit Isane with a pang. "Am I really… that lacking?"
"Of course not!" Kiyone giggled. "But Tachikawa's just too good. Everyone sees it. Honestly, I wouldn't be surprised if he becomes a captain soon. Then I could brag that my brother-in-law's a captain!"
Because Shin had healed Ukitake's illness, Kiyone already had immense gratitude toward him—and liking him was easy.
Isane's heart was in turmoil. Her feelings toward Shin had always been unclear—but today had pushed her further than ever. She was leaning toward saying yes… but she hadn't prepared herself for any of this.
"…I'll think it over," she muttered.
"What's there to think about?" Kiyone leaned in, eyes sparkling. "And you better keep in mind—there's definitely other girls in your squad eyeing him!"
That jab hit hard.
Yes… someone as outstanding as Shin—others were bound to notice him too.
If she hesitated too long, what if someone else swooped in?
No, that wouldn't happen. Right? Shin had already expressed his feelings, hadn't he?
Her thoughts spiraled. Then she whispered, "So… what should I do? Wait for him to confess again?"
She thought back to their embrace earlier. If Kiyone hadn't walked in, what would've happened? Would Shin have kissed her?
Her face flushed again at the thought.
Kiyone was already planning for her. "Didn't you say he confessed just now? And I interrupted it, right? Then it's bound to happen again. Probably tomorrow."
She grinned. "And when it does, just say yes."
"…"
Isane's cheeks burned hot. She pressed a cool finger to her face, but it didn't help—the heat was rising from inside.