The weekend sun was shining brightly as Kazuki relaxed at home, quietly flipping through a magazine in the living room. He was enjoying the rare peace and quiet until he heard the front door creak open, followed by the sound of footsteps padding toward him.
"Kazuki!" a familiar voice chimed, breaking the stillness.
Kazuki looked up to see his little sister, Aoi, bounding into the room. She was a bundle of energy with an ever-present smile, her eyes bright with excitement. She had her hair styled in a cute bob and wore a casual outfit, a clear contrast to her usual school uniform. Despite the four-year age gap between them, Aoi had always clung to Kazuki with an almost fierce loyalty.
"Onii-chan!" she said, practically throwing herself onto the couch beside him. "You're finally not busy. I thought you'd be spending the weekend with Shizuka or something…"
Kazuki chuckled, patting her head affectionately. "Well, I'm here now. What's up?"
She grinned, leaning closer as if to stake her claim on him. "Just wanted to spend some time with my favorite brother! Can we go out somewhere? Just the two of us?"
Before Kazuki could respond, a knock sounded at the door, followed by the entrance of none other than Shizuka. She strolled in casually, her silver hair catching the light, her usual confident smile on her face as she greeted them.
"Oh, hey Kazuki! And… hi, Aoi!" Shizuka said with a bright smile, giving a little wave.
Aoi's friendly expression instantly morphed into a pout. She shifted closer to Kazuki, clutching his arm possessively. "Oh, it's you, Shizuka. Here to take up all of my brother's time again?"
Shizuka raised an eyebrow, sensing the tension but not one to back down from a challenge. She smirked, crossing her arms. "Well, it's not my fault Kazuki enjoys my company, is it?"
Aoi's eyes narrowed, and she huffed, squeezing Kazuki's arm tighter. "You can't just show up whenever you want, you know. Onii-chan and I had plans today. *Right*, Kazuki?"
Kazuki looked between the two of them, surprised by the sudden rivalry. He had always known Aoi had a bit of a clingy side, but her intense reaction to Shizuka's presence was new.
"Oh, uh, well, we hadn't actually decided on anything yet," Kazuki replied, trying to keep the peace. "Maybe we can all hang out together?"
Shizuka grinned, leaning in closer to Kazuki from his other side. "Sounds like a great idea to me! I wouldn't mind spending more time with my favorite guy."
Aoi shot Shizuka a glare. "Well, I *would* mind. He's *my* brother, after all, and we were supposed to have some sibling bonding time!"
Shizuka shrugged, unfazed. "Oh, come on, Aoi. There's plenty of Kazuki to go around."
Aoi tightened her grip even further, her face tinged with a hint of red. "Well, I'd rather have him to myself. It's not like he's *your* brother."
Kazuki sighed, watching the two girls with a mix of amusement and slight exasperation. He cared deeply for his little sister, and he valued his time with her — but Shizuka was important to him, too. He hated to see them squabble, especially over him.
"Alright, how about this?" Kazuki suggested. "We can spend the morning together, Aoi, just like you wanted. And then later, if Shizuka wants, we can all grab lunch or something. That way, everyone gets some time."
Aoi's expression softened, and she reluctantly released his arm, glancing at Shizuka with a mix of wariness and satisfaction. "Fine, I guess that works… But only because you said so, Onii-chan."
Shizuka chuckled, giving Aoi a playful look. "Looks like I'll just have to be patient, then. Don't worry, Aoi, I'll let you have some alone time. Just don't get too greedy with it."
Aoi stuck out her tongue, but then turned back to Kazuki, tugging at his hand. "Come on, Onii-chan! Let's go out before someone tries to steal you away again."
Kazuki laughed, ruffling her hair. "Alright, alright. Let's go. Shizuka, I'll see you later?"
Shizuka waved cheerfully, watching them head out. "I'll hold you to that, Kazuki!"
As Kazuki and Aoi stepped outside, she held his hand tightly, looking up at him with a satisfied smile. "You know, Onii-chan… I really like when it's just the two of us. You're mine, after all."
Kazuki chuckled, though he couldn't help but feel the tiniest bit of awkwardness in her possessive tone. "I know, Aoi. But you know Shizuka's important to me, too."
Aoi frowned slightly but nodded. "Yeah, I know. I just… I don't want anyone taking you away from me."
Kazuki gave her a reassuring smile, squeezing her hand. "You don't have to worry about that. You'll always be my little sister. No one can change that."
For the moment, Aoi seemed content, and as they spent the day together, Kazuki enjoyed the time without any tension. But in the back of his mind, he wondered how long he could keep the peace between his little sister and his best friend — and if this rivalry was something he'd just have to get used to.