The sea outside the window was awash with the golden-red hues of twilight—neither of day nor night, but the color of boundaries. Just as this sea belonged neither wholly to Proper Human History nor to any Lostbelt.
Steve quietly listened as the girl beside him spoke about her childhood.
It was a story completely different from the gloomy, oppressive Atlasia in his memories.
In this world, Sion still bore the immense legacy of Atlas Institute and found it hard to fit among her peers due to her precocious nature—but her world was filled with sunlight.
Her foster father, Zepia, was eccentric, but he never disregarded her growth. Even in awkward ways, he showed his care. She didn't have friends to talk with all night, but she also never faced malice intent on stabbing her in the back.
She was free.
She was optimistic.
She was a pure idealist who believed, so long as the calculation was precise enough, she could solve all of the world's mysteries.
It was as if, after countless days and nights filled with wounds and shadows in a hopeless world, Steve personally watch the version of her before his eyes now—one nurtured by kindness and patience that needed neither fixing nor gentle protection, because she already shone brightly on her own.
Steve felt relief from the depths of his heart. It was like an old gardener seeing a flower he once struggled to nurture now bloom in flawless beauty in another garden.
And yet... precisely because her radiance was so dazzling, the shadows hidden in her future also seemed more striking.
Steve's eyes lowered slightly, focusing on Sion's excitedly gesturing hands—still warm and lively.
But in the original script he knew, those hands belonged to someone who had already written an incredibly cruel ending for herself.
Out of a desire to fight the Alien God, to offer a final haven to Chaldea's perishing saviors, and to elevate fleeting happiness gained during festivals into reachable daily life, this seemingly optimistic fool resolved to sacrifice herself.
She tried to forcibly bind her own causality to the concept of loser, just so that, in a despairing situation where all of human reason stood on the brink, she could allow Chaldea to take what little resources and time remained.
But this, too, came at a price.
When all was over, and Proper Human History restored, as frozen time melted, everything belonging to Lostbelt would be corrected and repaired—including her.
She, like the inhabitants of the Lostbelt, would quietly disappear before the dawn.
Her existence, cut from causality, might disappear even from the memories of Chaldea's people.
She would walk alone toward a bad ending, quietly granting someone else's happy ending from a forgotten corner nobody remembered.
What was this, really? Self-pity? Or perhaps the pure efficiency mentality of an Atlas alchemist?
If Steve had simply watched, he might have admired their willingness to sacrifice personal interest for the great cause.
But now, seeing the girl before him laugh, he felt nothing but uncontrollable anger: anger toward her unfair fate, exasperation at her willingness to manage herself away.
"...Sion."
He cut short her reminiscence. His voice was not loud, nor did it carry the pressure of a supreme commander. Instead, it was incomparably gentle.
Yet this unusual gentleness was what froze the smile on Sion's face.
"We've talked about the past—shouldn't we talk about the future, too?"
"Or rather... tell me your plan for this future."
For a moment, Sion's body visibly stiffened.
She turned her head, glancing around, unconsciously twisting her clothes with her fingers—a telltale habit when she felt guilty.
He remembered it well.
"Future? Of course! I've already got contingency plans to fight the Alien Gods!"
"If we can analyze the Fantasy Trees' structure and combine it with the Wandering Sea's special environment—"
"No, that's not what I mean."
Steve shook his head gently, gazing straight into her eyes. His deep eyes seemed to pierce her soul, seeing the secret at its very core. "I mean...about your own self-positioning."
"About how you plan to deal with your relationship to Proper Human History—and to Lostbelt."
Sion's pupils contracted sharply.
She opened her mouth in protest, but no sound came—as if cotton clogged her throat.
How did he know?
This plan was only in her mind—it hadn't even been fully input into her quantum calculation devices. It was her last trump card as Atlas' representative, prepared as the ultimate sacrifice for his optimal solution.
"What—what are you saying, Rider?"
"Of course I'm part of Proper Human History, and a future member for Chaldea—"
"Haven't you already begun severing your ties with Proper Human History?"
Steve pressed on, not giving her a single breath's respite, every word as casual as asking "What's for dinner?"—yet each one struck her defenses like a hammer.
"To deceive the world's corrective force, to become a bridge between the Lostbelt and Proper Human History—or, perhaps, to become the sacrifice."
"You intend to burn yourself as fuel, so Chaldea's little boat can attain more materials through this chaotic era, right?"
"..."
Sion fell completely silent, head bowed, her eyes hidden by her bangs. The slight trembling of her shoulders and the death-grip on her knees spoke of her inner turmoil.
He had seen right through her.
Before this Heroic Spirit from the future, all her calculations and showy confidence seemed as clumsy as a child's prank.
"...That is the optimal solution."
After a long silence, she finally forced out those words in a soft voice, yet one filled with heart-wrenching stubbornness.
"The power of the Alien God is beyond imagination."
"Proper Human History has been wiped blank; we are fighting against the entire will of the Earth."
"If we can't exploit every loophole, can't pay the necessary costs—there's no way Chaldea can possibly win."
"My sacrifice is... a probabilistic necessity."
"If I can see that future realized—if everyone can survive..."
"That's the result of your calculation, Atlas' genius."
Steve sighed.
He reached out, gently but firmly lifting her chin to make her look at him.
His eyes held no rebuke—only a kindness and determination sufficient to move her to unconscious tears.
"Listen, Sion... I don't deny your calculation skills, nor do I deny the nobility of your sacrifice."
"But aren't you forgetting the most important variable?"
Variable?
Sion met his gaze, mind blank.
"That's me."
Steve smiled faintly—a smile brimming with calm confidence, the sort that could hold up the sky with a single hand should it collapse.
"The one you summoned is no mere Heroic Spirit. He's the man who took humanity to the stars, who rewrote a hopeless future into a legend of hope in another world."
"If you called me to this world, placed me under your command by destiny—then I will never permit such a trivial bad ending."
His fingers traced the silhouette of her cheek, his voice soft yet unyieldingly strong.
"Throw every necessary sacrifice and so-called optimal solution in the trash."
"In my calculations, the only outcome is that everyone survives."
"Whether it's the boy from Chaldea, the demi-servant girl, or you—Sion Eltnam Sokaris."
"No one gets left behind."
"But... that's a matter of causality—"
"Causality? Who cares about that?"
Steve cut her off smoothly. "I'll help you."
"We'll save the world together. Not just human history, but you, too."
"With my Noble Phantasm, my wisdom, and even unreasonable Cosmic Magecraft, we'll smash that so-called sacrificial ritual to pieces."
He let go of her cheeks, but then gently wrapped her cold hand in his, passing on the warmth of his palm.
"So, forget that ridiculous self-sacrifice plan."
"From now on, your duty isn't to become a tragic hero—but to stand at my side as my master, and watch as together we reshape this unfair world… understood?"
Sion stared at him in a daze, tears already overflowing.
She had always believed she was alone, bearing this burden by herself.
She was used to controlling her emotions with reason, viewing sacrifice as a mere calculation.
But now, someone was telling her: You don't have to do that. You're someone worth protecting, someone indispensable for a happy ending.
This feeling... was so unfair.
"...You... overbearing... foolish servant—!"
She sniffled, struggling to keep her dignity, but her voice was already choked with sobs.
"If you're going to say that... if you're making such bold claims... then—for now, at least—I'll try believing in your calculation."
"But! If in the end we still fail—if it just doesn't work out—then I... I'll hate you for it!"
"Any time. But I won't give you the chance."
Steve smiled, wiping away the tears from her eyes. "In the end, no matter the world, letting your wife cry is always the greatest shame for a man."
This time, Sion did not deny the title of wife.
She only blushed again and looked away, but gripped his palm tightly.
Bathed in the golden-red radiance, the distance between their hearts closed even further.
...
PS: Read at least 67 advanced chapters at patreon.com/AbsoluteCode