"Compared to the first world that was already destroyed, the second world managed to survive—thanks to a certain twist of fate."

If the first world had perished to an unknown threat, then the "second worldline" Dr. Romani spoke of must have been the world of Sensei Hoshino, ten years later.

"The second world, which should have been destroyed by Paradox, was instead saved because of your accidental time travel, Chiyuki. You still remember, don't you?"

Hoshino pointed to herself uncertainly. "So… I was the one who saved it?"

True, both she and her future self—the Sensei—had once fought Paradox together at Duel Academy. But to be honest, Hoshino had always felt like little more than a useless accessory in that battle. From start to finish, it was her future self who had carried the fight.

"Any factor that deviates from the world's original course can alter its worldline. If you hadn't crossed over back then to help, Duel Academy in that world would have been destroyed by Paradox and his Duel Monsters."

At the time, Paradox had sealed away the Heroic Spirit Monsters that the future Hoshino relied on. Without Chiyuki's timely arrival, her future self would never have been able to unleash the power of her Magical Girl deck and defeat Paradox in a team duel.

Dr. Romani's gaze grew complicated as he continued. "But the second world… had a decisive difference from the other two. Even though it survived Paradox, it remained nearly powerless against the unknown threat."

"A decisive difference? Oh, I know! (･･´ﾒ) In the future I end up way too curvy—totally sexy!"

"…Heh, well, you could put it that way~"

Scratching his cheek with an awkward smile, Dr. Romani went on. "In the second world, for some reason, you never awakened the power of Atlantis. Your growth remained completely normal."

"I knew it! All Atlanteans must be a bunch of perverts! Otherwise, why would awakening the bloodline make us age backward!?"

Now convinced she had discovered the culprit behind why she could never grow into her future-professor self, Hoshino fumed.

"╰(‵□′)╯ Fine then! I won't awaken it! Just give me back that curvy figure already!"

Kaiba turned his head with a cold snort. "Hmph. You, of all people, daring to wish for such a figure."

"Why are you laughing, Kaiba? So what if Kisara has a nice body? Is that really something worth bragging about?"

…That wasn't even the point!

"Listen, Chiyuki~" Dr. Romani quickly cut in, forcing the conversation back on track. The discussion was supposed to be serious, yet with Hoshino around, it kept veering wildly off course, making it impossible to stay solemn.

"Even if I couldn't identify the enemy with Clairvoyance, I understood one thing clearly: if you can't master the power of Atlantis, victory is impossible."

"The power of Atlantis… Doctor, do you mean the one I used in the Memory World? If that's it, I can't use it anymore."

Ever since she had returned from the Memory World, Hoshino had searched through her deck but never found the Atlantis card again. Not that it mattered—its effect was so ridiculously overpowered, it would've been banned forever in any real duel.

Romani shook his head gently, smiling. "The power of Atlantis lies dormant within your bloodline. You can't use it now simply because the time hasn't come. But in a future battle, it will be the key to overturning the fate of destruction."

"Wait, Doctor. When you say 'future,' just how far in the future are we talking?"

If even ten years later there was still no sign of this unknown enemy, then did "distant" mean twenty or thirty years? Fifty or sixty? Even if her body never aged, wouldn't her mentality eventually turn into that of some old granny?

Romani tilted his head thoughtfully, then replied, "If I had to guess… about four or five hundred years~"

"Four or five hundred years?!"

Hoshino shrieked. The answer was ten times further than she had expected.

Forget four or five hundred—she could barely imagine the twenty-second century, a hundred years from now. Would there really be cat-shaped robots with four-dimensional pockets by then?

"If I really live that long, won't I just turn into some kind of ancient monster?"

Suddenly realizing the gravity of it, Hoshino held her chin, muttering to herself. "No, wait… could this be the so-called 'eternal youth'? Don't tell me the me I saw in the Time Tunnel was already approaching Scáthach-tier old hag levels!"

Arthur forced a polite yet awkward smile. "Master, your head looks about ready to be skewered by a spear…"

Dr. Romani soothed her. "Living for centuries is nothing unusual for a Heroic Spirit. At first it may feel strange, but you'll get used to it. Immortality isn't as terrifying as it sounds. You just endure, and then it becomes normal."

The pure white space suddenly trembled faintly. Hoshino felt her body flicker with a sense of nothingness, realizing she couldn't linger in this dimension much longer.

"It seems my time is up. After all, I'm just a person who erased all traces of my existence. This is all I can tell you, Chiyuki~"

Romani's farewell carried a note of reluctance. Though Hoshino's interruptions had derailed the conversation again and again, he had cherished every moment. After so long without anyone to talk to, even her complaints and sarcastic remarks felt precious.

Perhaps, he thought, he still did have regrets… He still wanted to talk more with others. He still wanted to help this girl before him. He still wanted to fight side by side with everyone, like before.

Sensing the fleeting loneliness in his eyes, Hoshino's heart tightened. "Doctor… will we be able to meet again?"

"Of course," Romani affirmed. "The chance may be slim, but as long as it isn't zero, then on the long road of time, our paths will cross once more."

"You mean as long as I live long enough, I'll see you again? Then I'll do my best!"

"As expected of you, Chiyuki—that's a wonderfully straightforward way of putting it~"

As the dimension shattered under the holy sword, Hoshino and Kaiba's fading bodies began to correct themselves, returning to their rightful points in time.

Romani slipped a ring from his finger. It turned into a shimmering glow that merged with Hoshino's Duel Disk deck.

"And as a final parting gift… take this. It's nothing too precious, but it will help you—a proof that Solomon once existed."

—No, to be honest, it's more for myself. Once, I threw away all that I was as Solomon. But now, I want to leave behind a trace of myself by her side.

Even if I can only ever watch from this place of "nothing," just knowing that my power may one day become Hoshino's strength… In that instant, Romani Archaman felt as though he had returned once more to Chaldea—to the seat that was always his.

…

Blue-Eyes White Dragon Dome, Duel Arena—

"Back again? This time…"

After briefly losing her vision, Hoshino opened her eyes once more to find herself surrounded by the noisy, bustling atmosphere of the press conference.

"The doctor said that once the Dimensional Cube was destroyed, we'd return to the proper point in time. So… what time is it now?"

"Holy Lance—Anchor Unleashed! This is the radiance born from the prayers of the Knights of the Round Table, our phosphorescent starlight leading to the end! It can rend the sky and pierce the earth!"

Mash's desperate shout snapped Hoshino's attention toward the duel. A powerful sense of déjà vu surged through her mind.

"The correct point in time… don't tell me?!"

[Mash Kyrielight Ortinax ATK 4000 → 8000]

"Take this! Storm Anchor—Shining Spear of the Faraway End!!!"

[Seto Kaiba LP 3500 → 3400]

The black holy lance pierced through Blue-Eyes Shining Dragon, followed by a blazing surge of solar radiance. Time, rewound and transmitted from a higher dimension, froze at the decisive final turn of Hoshino's duel against Kaiba.

"Hahahaha! Looks like my Master came out on top this time, Seto~"

[Seto Kaiba LP 3400 → 0]

"This moment in time… in a sense, it really is the most appropriate one."

With his Life Points reduced to zero and his mind eroded by the Cube, Sera was no longer able to interfere. The Dimensional Cube's destruction had unraveled its hold over time itself. Thus, nothing remained to disrupt the duel. Hoshino had earned her very first true victory against Kaiba.

[Duel Over! Winner: Chiyuki Hoshino!]

"She did it! Nee-san (Sensei) Hoshino really did it!"

Akasha and Jaden leapt into each other's arms, overjoyed to the point of forgetting themselves. Their excitement was so overwhelming that Jaden didn't even realize this was one of the happiest moments of his life.

"You really fought hard, Hoshino! That was one hell of a duel!" Yugi exclaimed in admiration.

"Sniff sniff sniff~" Mana twitched her nose and teased, "I think I can smell it… the concentration of Prince in the air definitely went up."

Atem turned to his partner. "That instant just now—it seems the seal binding my soul has been undone. If you want to switch places again, there should be no problem."

"The moment Hoshino won, it was released?" Yugi thought for a moment, but no explanation came to mind. "I don't really understand why, but it's wonderful that you're free again, other me."

"Talk about a comeback at death's door—that's the willpower of the Duel King for you!"

"Unbelievable. To think that even after losing to Yugi, Kaiba would suffer defeat again at the hands of the Duel King."

"A duel between the White Dragons and Mash, huh? That was one for the books."

Lowering his Duel Disk, Kaiba could only reflect bitterly—it was already the third time today he had experienced defeat.

"You've won, Hoshino. You not only bested me, but secured this dimension in its moment of crisis. Today's victory belongs to you alone."

It felt like a dream. Until now, something had always intervened before Kaiba could be truly defeated. Now that real victory lay before her, Hoshino almost doubted it was real.

"Admitting defeat so cleanly? Then Kaiba, don't you dare go back on your word. You remember our promise from two years ago, don't you?"

"Hmph. I never break my word. What comes next is the real highlight of this press conference."

Kaiba narrowed his eyes, a satisfied smile tugging at the corner of his mouth.

"Everyone, prepare yourselves for the dawn of a new era of Duel Monsters—!"

(***)

Five years later—

"Crap, I overslept! I'm gonna be late for the entrance exams!"

"Calm down, aibo. You're not the one taking the test, so what's the rush?" Hoshino Alter chided.

"Yeah, exactly. I'm the principal, damn it! Who cares about some entrance exam?"

Flopping back under the covers, she went for a second round of sleep. As the honorary principal of Duel Academy, all she really had to do was show up after the exams and give a short speech. Between the written and practical tests, she still had a good two hours left to sleep.

"What a cushy job. And no more debts hanging over my head either. Honestly, this kind of peace just makes a person lazy… zzZZZ~"

"Wait, wait, don't go back to sleep, aibo! Sure, you being late doesn't matter, but today's Akasha's entrance exam! Didn't you say you'd go cheer her on?"

"Well, yeah, I might've said that… but now that I think about it, wouldn't the principal personally showing up to support one student just make people think Akasha got in through favoritism?"

"I can't shake the feeling that's just your excuse to keep sleeping. If that girl throws a fit later, don't expect me to switch places and take the blame for you, aibo!"

Two years after Kaiba officially announced the academy's construction, Duel Academy finally opened its doors. That made this year's batch the third generation of incoming students, with the very first class now entering their senior year.

And Kaiba had indeed kept his word, appointing Hoshino as honorary principal.

Of course, being "honorary" meant the title was mostly in name only—her actual responsibilities were minimal. The bulk of administrative work and public affairs fell to Principal Sheppard.

Yes, that Sheppard—the bald old man once known as "King," who had lost to Hoshino's Cyber Deck in an underground duel. As one of Duel Monsters' early figures, and with close ties to Kaiba, having him serve as the academy's acting head was more than reasonable.

Not that Hoshino minded—far from it. She was never the type to chase fame or power, and the arrangement left her blissfully free of real work.

Seeing Sheppard's hair grow thinner by the day under the academy's heavy workload only made her silently grateful that Kaiba had looked out for her.

"(|3[____] Guess I'll pray for world peace while I take another nap. Ahh, peace really is the best~"