Just as he had said when he first designed a performance outfit for Hoshino Ai, Tetsuya had, in fact, always felt a sense of guilt towards her.
When he was being cared for by the Chihaya family, he would always worry if she was still living in a hell similar to that orphanage.
As he gradually obtained the things he had always dreamed of, he would always think how wonderful it would be if Ai could receive the same miraculous salvation.
And the thing that he found most difficult to let go of was, of course, his failure to find her back then:
"If I hadn't been running around aimlessly like a headless fly, but had been more methodical, investigating other welfare institutions, could I have found you sooner? If I had pleaded more sincerely with the adults at the police department, would they have made an exception and told me where you were? If I had just kept searching for you, could I have found you before your spirit was completely exhausted?"
Tetsuya murmured, looking back on that regret-filled past with an almost penitent attitude.
"I've always known. You relied on me, and you trusted me. And I have always one-sidedly used your reliance on me as my motivation to keep living... Without you, I might not have lasted until the day I met the Chihaya family."
"I know, Ai. You must have been so lonely, so sad during the time you lost me, right? I'm sorry... If only I could have found you sooner, I probably wouldn't have pushed you to this point, would I?"
He kept his eyes tightly shut, speaking in a tone of utmost sincerity and remorse.
"If that's the case... then, as long as it can calm this anxiety that has lasted for seven years, I'll do whatever you want."
...
After listening to Tetsuya's confession, Ai's once chaotic mind was instantly left with only a single voice—
(Why is HE the one apologizing?)
(Does he have any idea what's going on? I'm the one using force on him! Not only did I not get his consent, but I was even planning to selfishly take away everything he's worked so hard to build. Why isn't he stopping me, or blaming me, but apologizing to me instead?)
(Couldn't find me sooner? Isn't that perfectly normal? For a twelve-year-old boy who had never even been to school, what he did was already more than enough, wasn't it?)
(Is it because he's always been this strict with himself? Or... am I really so important to him that he's carried this guilt for seven whole years?)
Just then, Ai was suddenly reminded of the pajamas that had been delivered along with that performance outfit.
It was through those pajamas that she confirmed that not only had Tetsu not forgotten her, but he had even kept the memories between them close to his heart.
And now, looking back at those two outfits, was what they contained really just simple longing?
While she had endured seven years of loneliness and anxiety by herself, what had this person, who was always thinking of her, been thinking?
The feelings he held for her... were they really, as she had once thought, feelings that anyone could easily replace?
If his feelings were truly that shallow, would he really be so willing to offer up everything that was his, just like this?
...
"...Tetsu."
Ai, who had been silent all this time, suddenly called his name.
"To you, what kind of existence am I?"
"...I don't know either."
Tetsuya's voice was full of confusion.
"Actually, since seven years ago, I've never been able to figure out what kind of relationship we have..."
They weren't family, nor were they simply friends.
They relied on each other, depended on each other.
For the Tetsuya of that time, he never understood how to explain this strange feeling.
"Did you know? At first, I really wanted to be your little sister."
Ai said in a low voice.
"Because you said you needed affection and a family, I always wanted to fulfill your wish. But... you rejected me. And you said you didn't want any lies in our relationship."
"That's right. Back then and now, I could never simply see you as my sister."
Tetsuya said truthfully.
"A sibling relationship should be purer, an almost instinctive desire to protect and care for someone... But for me, while I was taking care of you, I was also deeply dependent on you. That kind of need is not a feeling that should exist between siblings."
"..."
Ai was silent for a long moment before asking:
"Does that mean... seven years ago... you saw me with feelings that were more 'impure' than that of a brother?"
"...Yes."
Tetsuya nodded in admission.
"Compared to my current understanding of familial love, those feelings could indeed be called 'impure'."
"I see..."
Ai whispered softly.
"So that's how it was. It wasn't because I was no longer needed, nor was it because I was replaceable..."
In fact, the truth was the exact opposite.
Although she wasn't his family and couldn't provide the affection he had always dreamed of, in reality, seven years ago, he had been seeking another kind of feeling from her—a feeling that he still couldn't understand to this day.
Meanwhile, Ai's voice, which made it difficult to discern whether she was happy or sad, caused an indescribable nervousness to well up in Tetsuya's heart.
"...Are you disappointed in me?"
He couldn't help but ask.
"I'm not the selfless person you imagined me to be..."
"...Yes, I am very disappointed."
Hearing this, Tetsuya felt a chill rise from the bottom of his heart.
However, in the next second, Ai's following words made the sentence he was about to say get stuck in his throat.
"If I had confessed to you more seriously, more resolutely seven years ago, maybe we would have been lovers by then..."
Ai's voice was filled with regret and lament.
"If that's the case, then I can't blame anyone, can I? It was entirely because of my own indecisiveness that I pushed you towards Anon and Sakiko..."
"Eh? Wait, Ai, what are you talking about?"
Finally, hearing this bizarre self-reflection, Tetsuya opened his eyes.
"What do you mean, your indecisiveness? What is—"
"I really messed this up... Ahh, I completely messed it up."
As Ai spoke, she picked up the box of safety supplies.
Just as Tetsuya thought she was about to open it, she stuffed it back into her pocket instead.
"But it's a good thing you're a slow, clueless idiot. So, before I explain everything to you, I need to confirm what you said one more time... You did just say, 'as long as it can calm this anxiety that has lasted for seven years, I'll do whatever you want,' right?"
"...Yes."
Tetsuya nodded again in confirmation.
"As long as it puts you at ease, I'll do any—mmph!"
The unfinished sentence was forcefully stopped.
Like a non-Newtonian fluid, it shifted from hard to soft, from resistance to silky smoothness—
Crossing seven years of remorse and regret, it finally culminated in this touch that lasted seven seconds.
And with that, this rehearsal could, at last, be declared a success.