Phew... Let's try to think about this rationally.
February 29th... It's probably not the name of that specific folder.
Besides, that isn't the kind of thing one brings up in a room full of adults anyway.
In that case, it must be a different February 29th... Could it be the day of the retirement ceremony?
That day fell on February 29th as well.
Come to think of it, I was told that Bianca was seen leaving the Captain's quarters on the Hyperion looking completely disheveled on the day of my retirement.
Since there was an eyewitness to that suspicious scene, that must have been the day we... had our encounter.
But that creates a massive logical contradiction.
That night, while I was spending a passionate evening with my wife, I briefly stepped out to the Hyperion's Captain's quarters to retrieve a HOMU fountain pen she had gifted me.
I confirmed that only two minutes had passed upon my return, but in reality, two hours had ticked by.
One might ask if I had fallen under the influence of Fenghuang Down, but... I've always been naturally resistant to its effects.
The Class Monitor herself once said that even if I were caught in its web, my mental fortitude and clarity are strong enough that I'd realize it almost immediately and break free.
Furthermore, the wristwatch I was wearing makes that theory impossible.
Even if it were Rita or Senior Mei, they wouldn't be able to bypass my watch's security lock.
The passcode was my date of birth from my previous life.
And yes, that includes the year.
It's a password that has absolutely nothing to do with my current identity, which is why no one has ever been able to crack it.
...Now that I think about it, I should have locked that 'February 29th' file the same way.
Well, what's done is done. Let's move on.
Regardless, the critical point is that my watch is synced to my terminal, and because the lock remained engaged, it proves no one tampered with it.
This is definitive proof that I wasn't under the influence of Fenghuang Down.
Sure, one could argue that someone might have figured out the code and unlocked it anyway.
But I had configured it to log every instance the security was bypassed; I would have noticed the anomaly immediately.
Since no such log existed, I can be certain nothing was wrong on that front.
Then what if Fenghuang Down was used to deceive everyone aboard the Hyperion at once?
A single feather has a limited range. Furthermore, there were people on board trained by Otto himself who knew exactly how to bypass the Divine Key's influence. They would have noticed and alerted me instantly.
So, that hypothesis is out too.
What about a localized space-time storm occurring exactly when I entered and Bianca followed?
If that had happened, the sensors would have spiked, and the science team would never have let it slide.
They would have swarmed the area with every piece of equipment they owned to investigate the phenomenon.
In that scenario, I would have bumped into Bianca and the others while they were searching for me, or they would have found me directly.
But that didn't happen that day.
Some might suggest alcohol played a role, but... how should I put this? Because of their youthful appearance, people generally don't let them drink much in public.
Specifically, Mr. Welt, who is all too familiar with their drinking habits, watches them like a hawk to prevent them from touching the bottle.
I remember asking him once, "Is one glass really so bad?" only for Mr. Welt to massage his temples as if suppressing a painful memory. "That one glass is enough to finish them," he replied. I could only nod awkwardly and concede, "I suppose it can't be helped then."
Still, isn't their tolerance a bit too low, dear Doctors?
"...Still haven't caught on?"
"...Sigh. No, actually, I have one theory."
Right. Time to stop running from reality.
To be honest, a hypothesis had formed in my mind the moment I heard that Bianca was only thinking 'in one direction.'
But this theory felt so absurd at the time that I thought it would be faster just to try and read Bianca's mind instead.
It may seem impossible in the present, but from a future perspective, it might just be feasible.
However, it requires fulfilling one specific condition... and it seems that condition has already been met.
The wristwatch I was wearing was the proof.
The reality where I thought only two minutes had passed, while in truth, two hours had gone by.
They said Fenghuang Down was used on Siegfried, so it likely wasn't used on me.
If they had used it on me, there wouldn't have been a feather left over.
Or rather, they wouldn't have had enough power left to ensnare someone like Siegfried after dealing with me.
And if they had tried, the situation would have turned into a chaotic mess long before that.
So the question remains:
Why was the Fenghuang Down, which was originally intended for me, never used?
The answer is simple: Because there was no longer any need for it.
"It sounds like something out of a dream, but it's not entirely impossible. Is it, Bianca?"
"Yes."
"That day... you didn't travel to the future. Well, technically, there is no way to travel to the future from our current point in time."
"You would know that better than anyone."
"Exactly. But you said it, didn't you? That I was only thinking in one direction."
"Yes. You weren't acting like your usual self."
"I guess I'm just getting old. My brain is starting to hit roadblocks."
I let out a heavy sigh and scratched my head. Then, seeing the children staring up at me intently, I smiled and gestured for them to come over.
The girls looked at each other, beamed radiant smiles, and dashed toward me, throwing themselves into my arms with a muffled 'oof.'
Feeling their weight—more substantial than before—and their boundless energy, I couldn't help but grin.
That extra weight and energy meant they were eating well and growing healthy.
I gently stroked their hair as they nestled against me, and continued speaking.
"You... on that day—"
As I finished my sentence, everyone's eyes widened. Bianca, who had maintained a stoic expression until now, blossomed into a vibrant, radiant smile.
"As expected of you."
"'As expected' my foot.... Haaa, well, at least all my questions have been answered."
Back when I was researching time at the Imaginary Tree, I was puzzled by why Otto Apocalypse had completely vanished from existence.
It was an experiment I had conducted myself—a desperate attempt to save Major Himeko in the past while being fully prepared for my own erasure.
Back then, before my wife had even confessed to me, I was a bit reckless with my own life. I just wanted to save my teacher, no matter the cost.
The result wasn't a change in the future, but rather the creation of a new parallel world.
But a question haunted me: why didn't I disappear like Otto Apocalypse did?
How was I able to return safely while he vanished?
While investigating the specific timeline Otto visited via the Imaginary Tree to save Kallen Kaslana, I discovered the truth.
In the original history, Otto witnessed Kallen's death at the hands of a Honkai Beast, a regret he carried for a lifetime.
But when Otto threw his current self into the past to change that outcome, a Time Paradox occurred.
His past self and his present self occupied the same time and the same space simultaneously.
Because of this, the Imaginary Tree rejected the anomaly. It cannot tolerate the existence of the same individual in the same place at the same time, and thus, it erases that existence entirely.
The problem is that this erasure doesn't just apply to the 'present' self; it ripples back to the 'past' self as well.
I confirmed this through numerous tests with lab animals, so I knew it to be a cold, hard fact.
...Well, even if the existence is erased, the memories aren't necessarily wiped away.
That's why Kallen Kaslana was able to say, "Goodbye forever, my inventor," to the fading Otto.
When I went to save Major Himeko, I didn't know this. I only survived because my past self had been pulled into the Imaginary Space by the Herrscher of the Void at that exact moment. If not for that coincidence, I would have been erased on the spot.
"Then, I'll need a detailed explanation of what happened back then."
"Understood. I shall explain the events of that day."
As she spoke, Bianca stroked the head of Selene, who was sitting in my lap alongside Bronie, happily munching on snacks provided by Cecilia.
"It is as you suspect. That day, in the Captain's quarters, I encountered your future self—who had swapped places with the you of that timeline."