So they went out to the hallway to avoid waking Shirogane Miyuki.
Luckily it was still summer, so they didn't need to worry about catching cold. The night breeze brushing their faces was far more refreshing than the airless room.
"If something's on your mind, just ask, Kei."
Rinji smiled.
"Staying up late isn't good for your health, you know. Better to sleep early."
"…Rinji-nii."
Kei seemed hesitant. She didn't know how to bring it up.
"Hmm?"
"Now that you have a girlfriend… are you going to abandon me?"
"…???"
Rinji was utterly confused. That sounded like he'd done something horrible to her.
Realizing her wording was off, Kei quickly corrected herself.
"No, I mean… will you still care about me the way you used to?"
"Of course." Rinji smiled.
Hearing that made Kei feel relieved.
Rinji reached over to pat her head.
"I'll always care about you, Kei. You're my little sister—now and always."
"I wish that wasn't true in the future…"
"Huh?"
"N-Nothing."
Kei looked down quietly.
She didn't have any weird or selfish plans in mind. Like her brother Shirogane, she wasn't the kind of person who would hurt others for her own benefit.
Rinji had always been kind to her and treated the family well. She cherished that warmth.
Maybe that's why, when she found out Rinji didn't have a girlfriend, she thought: How nice it would be if that warmth could stay by my side forever.
But within one summer, Rinji had already gotten a girlfriend.
If that wasn't disheartening enough, the worst part was learning that he'd basically accept anyone who confessed to him.
Fast hands win. Slow hands lose. She missed her chance because of her own hesitation.
And her brother Shirogane—he knew what Rinji was like. If he had just told her earlier, maybe she would have had a chance.
Even if she had the chance now to break Rinji and Karura up, she wouldn't. That would be selfish and unforgivable.
But there was no way she could truly bless their relationship either.
"Rinji-nii, you said before that if someone confessed to you, you'd say yes, right?"
"Yeah."
"Then… if I had confessed back then… would it have worked?"
"No."
"…Eh!?"
Kei had never expected that answer.
Looking at her shocked face, Rinji explained, "It's simple. I would never get into a romantic relationship with a middle schooler. That'd be disgusting."
Back when he confessed to Hayasaka Ai in middle school, he was even younger than her. But now he was a high schooler.
"And besides, Kei, you're my little sister."
"…"
Finding out she never even had a chance to begin with—not just missed it—meant she couldn't really blame her brother for withholding info. But still, it was frustrating.
"And honestly, even if we did get together, I bet one day you'd walk away. Some things are better left never started."
"That's not true!"
Kei raised her voice in protest.
"Why would I ever leave…"
"I've killed people."
"…What?"
Before Kei could react, Rinji continued.
"Lots of people. And I haven't stopped."
"…You're lying, right?"
Kei gave a nervous laugh.
"Killing people… that can't be true. You're too kind for that…"
"What you see is just the surface. Just because I never showed you the cruel part of me doesn't mean it doesn't exist."
"…No way. Rinji-nii, you…"
"I told the President the same thing a long time ago—more than once. Not sure if he really took it in."
Rinji leaned against the railing and looked up at the black night sky and the bright full moon.
"Over six months ago, I was still in the Middle East. Constant conflict. I pulled the trigger almost every day. So many died by my hand, I stopped counting."
He lowered his head and looked at Kei, who sat speechless with wide eyes.
She had never imagined that the Rinji who always smiled kindly and treated them warmly had actually taken lives.
Maybe she still didn't believe him. Or maybe she just didn't want to believe it.
"Whether you believe me or not, I wanted to tell you the truth. Because that's trust," Rinji said. "If I lied now and you found out later, it'd be even harder to accept."
"…"
"There are times I really want to go back to the battlefield. Out there, there's no fake kindness or hidden motives. Orders and comrades—you can trust them. It's dangerous, but simple. That's why I stayed there for four years."
"Four years? You…"
"Yeah. I went there when I was twelve. Sounds crazy, right? A kid in a warzone. But honestly, the only thing that could really hurt me back then was this so-called peaceful society."
"…"
"That's enough talk for now."
Rinji walked past Kei with a smile and opened the door.
"You probably hate me now that you know what I'm really like. I bet you don't even want me to be your big brother anymore, but all of this—"
"Rinji-nii, is it because you trust me that you're telling me all this?"
Kei spoke with her head lowered, back facing Rinji so he couldn't see her expression.
"Yeah. I trust the President, and I trust you too…"
"Then I'll be honest with you too."
Kei suddenly turned around, walked up to Rinji, and slapped both her palms against his cheeks.
"Eh…"
"I don't hate you, Rinji-nii. I want to know you better. And… I like you. If you didn't already have a girlfriend, I'd be the one confessing to you."
"..."
This time, it was Rinji who was shocked.
"Kei…"
"And I'm not giving up either. I'll be in high school in less than two years anyway."
After saying all that, Kei dashed back into her room and slammed the door shut, leaving Rinji standing alone at the door, stunned by the whirlwind.