The Butterfly Effect

This is the husband. This is the wife. ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠This is the wife.

There is a saying about the butterfly effect.

The theory that the mere flutter of a butterfly's wings can spawn storms and disasters somewhere else on Earth. That even the slightest change in the past can send the future careening down a thousand different paths. And that, to prevent such uncertain upheaval, the past must be preserved as it was — that was the central idea.

Sophia, her veil discarded, had already drifted impossibly far from that orbit.

On impulse, she had infiltrated the training grounds disguised as a student. Just to see Mikhail. Just him. High-circle disguise magic ensured that no one noticed.

"…?"

No one — except the man wearing a face full of bewilderment.

Sophia felt her face melt like soft wax. How thoroughly must they have tormented him for him to neglect himself like this — hair sticking out in every direction, dark circles carved beneath his eyes!

She wanted to tear Arlea apart on the spot. That damned harlot of Babylon!

How dare she. How dare she, how dare she, how dare she corrupt my Oppa into this decadent wreck?!

"…That girl — why are her eyes like that? Mikhail! Be careful!"

"Understood."

The moment her gaze locked with Arlea's, Sophia lowered her wooden sword.

From Arlea's eyes, she felt a pitch-black darkness welling up. That is…

It was a human instinct — the primal sense that something before you was not quite right. A perception that pierced through to the essence of a ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠thing. And then Arlea's voice began to fill her head.

Too vivid to be mere telepathy, and yet not a single lip had moved. Sophia reeled at the sheer marvel of the technique.

You. Don't touch my husband.

Oh-ho.

Sophia's mouth stretched into a grin that climbed all the way to her cheekbones.

You dare call my Oppa your husband?

She could roughly piece together what was happening.

You regressed too, didn't you? To claim Oppa for yourself?

…

Sophia exhaled a cold breath.

So the others can regress as well. I thought it was strange how quickly you showed up. To think you'd be the culprit behind that magic.

Watch your tongue. Spouting such insolence at the Empress of the Empire.

A monster who ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠tormented my Oppa has no right. One fireball is more than enough for the likes of you.

Now that they had returned to the past, what did "yours" or "mine" even mean?

It was the same logic as an empire sending troops to seize any vacant territory on the continent. Whoever plants their flag first owns it.

"Wh-what?! Professor Sophia! How did you—"

Carlos, standing at the edge of the platform, never finished his sentence. She knocked him out with a Circle spell. By the time he woke, he wouldn't remember any of this.

"S-stop her!"

"Protect Her Highness!"

The same went for the assistant instructors gripping their swords. The students, too. Too many obstacles made things tiresome — swarming in like insects.

Sophia stretched her arms toward Mikhail. If she couldn't hold him this instant, she felt she would go mad.

"Oppa… Listen carefully. Don't listen to that monster! I-I'll make you understand everything!"

"What nonsense is this."

Mikhail settled into a stance.

"You're being tormented right now. That thing is a demon wearing a princess's skin!"

"A demon…"

"Yes! A demon!"

"Demon or otherwise, I don't know you. I have no idea what you're talking about. Surrender immediately. Do so, and I'll spare your life."

"……What?"

He… didn't remember her?

"Oppa?! D-don't be ridiculous. You're lying, right?! You only ever loved me! D-don't you remember our first time?!"

Tears welled in Sophia's eyes. Those snow-white orbs ringed with dark circles announced her identity clearer than any name.

This is awkward.

I felt the blood rush backward through my veins. An unexpected variable had become reality.

Sophia Le Borsch. The most unpredictable woman in this entire game.

A mage born to one of the Empire's great houses. A tragic heroine discarded by her own family the moment she outlived her usefulness. In the end, she became a yandere who coveted me. But a question remained.

Why did Sophia retain her memories of previous cycles? And more than that — she had regressed even earlier than Arlea.

Before I could even process the question, Sophia broke into a loose, unguarded smile.

"Oppa. Hold me. I-I really worked so hard, you know. You can do that much for your little sister who loves you, right? Hm?"

Sophia lifted her arms in a fumbling, searching motion. A hazy stream of mana poured forth, boring straight into my skull.

Magic!

The instant I identified it, I clenched my teeth hard. Know thy enemy. Sophia was casting a spell right now — and figuring out which one wasn't difficult. Just recalling her personality gave me the answer.

"Brainwashing magic, no doubt. She was trying to enchant me with that."

I muttered to myself. Sure enough, Sophia's mana began seeping into my body. It raced through my veins like a two-ton truck with no brakes. Destination: the heart. Because the soul resides in the heart.

Thud—

Like a viper's fangs, the mana bit into my heart. The will to invade was ferocious. But it was fine.

Magic didn't work on me. Not anymore.

The real problem started now. A mage of Sophia's caliber would certainly assume her spell had worked.

"Oppa. You're clear-headed now, right?! L-look at me. That devil-woman is going to defile you and then throw you away like garbage!"

Sophia threw both arms wide toward me. Had she mixed illusion magic into the cast as well? No wonder they called her a genius mage.

"Y-you bitch! Give me my Oppa back right now!"

"There's nothing to give back."

When whales fight, the shrimp's back gets broken — or so they say. This was bad. If those two started fighting at full power, the situation would spiral out of control. Concurrent regression was already enough of a headache. They say a person's fortune is only a matter of time — and the old sayings never miss a single syllable.

"O-Oppa. Please come to me. I can explain everything. O-Oppa, please! If you won't come… then I have no choice either, Oppa. I-I'll take you by force if I have to."

Sophia fixed me with a stare, her shoulders hiked high. Mana gathered. The mana that collected was vast as an ocean — the kind of awe I'd felt only after living years in this world.

"You damned thing."

Bang————!

Arlea fired a crimson mana orb barehanded from her palm.

Whoosh—

Leaving a shockwave in her wake, she vaulted straight forward. A barrage of rapier strikes came crashing down.

"B-Blink!"

Sophia maneuvered to the side. Tch — a miss. I heard Arlea mutter. Every thrust of the rapier had been dodged. But if she hadn't dodged, she would have died instantly.

Arlea wiped the mud from her blade with her bare hand.

"Sophia Le Borsch."

"Heh. You know my name well."

"You. Just because you handle one type of magic well, you went and cast a regression spell on us?"

"Regression… magic?"

"Yes. Regression magic. I don't even want to ask how you did it."

"Weren't you the one who sent Oppa here?"

"What. What nonsense. Stop spouting garbage."

"I'm not talented enough to cast a grand magic like that, you know?"

Sophia glanced at me. She understood that I had regressed, but a flicker of pity settled in the eyes that looked my way. Mana dispersed another layer from Sophia's staff.

"Heh… For Oppa's sake, shall we reach an understanding first?"

"Fine."

Arlea made a show of consenting. Sophia narrowed her eyes as if the very sight of her was repulsive.

"Oppa. Just stay put a little while. Soon — very soon — I'll make you remember me."

Sophia cast her magic in a single breath.

"Sleep."

Thud—!

In an instant, the world scorched black. People toppled like puppets with their strings cut. I moved just as quickly.

Something I'd learned upon arriving in this cycle: I had a resistance to magic. An extremely high one, at that.

But I can't let them find out. I'll pretend to collapse.

I went limp in both legs.

Thud—————.

I crumpled to the training ground floor like an old man who'd just drifted off to sleep.

Once everyone in the training grounds had fallen asleep, Sophia and Arlea exchanged brief introductions.

"I am Arlea Kiessen. The light of the Empire, the reason for the Empire's existence, the Empire itself — a woman who may as well be a walking institution. The Third Imperial Princess."

"Sophia Le Borsch. As for an introduction… I-I won't bother with one."

Sophia nodded and laid a bridge across the conversation.

"B-by the way, even the divine race that rules the continent has things it doesn't know, it seems? Regarding regression magic."

"I know nothing of regression. This telepathy that pierces our minds is the same."

Arlea coldly tapped her temple with a fingertip. Tick-tock, tick-tock — she clicked the sound with her mouth.

Wait. Telepathy? What the hell is she talking about?

I watched the two of them through narrowed eyes. Could the heroines communicate psychically with each other? Before I could even form the question properly, the conversation continued.

"First. Answer my questions, mage."

"…And if I refuse? Without you around, I could monopolize my Oppa anyway."

"That would be pointless. It benefits neither me nor you right now. Someone is targeting Mikhail."

In stark contrast to the snarling fight moments earlier, the atmosphere had gone utterly still. Not peace — a windless sea. A deferred peace, knowing death would come someday. That was the nature of their relationship now.

"Targeting Oppa?"

Sophia narrowed her eyes. She still hadn't dropped her suspicious gaze.

"Yes. But let me make one thing clear. This world is mine."

"…"

At Arlea's declaration, Sophia's face darkened further. I couldn't grasp the full meaning yet, but it was probably related to the save file — some concept of "intrusion," perhaps?

Even if it was insane. There was no option for yanderes to genuinely cooperate with each other. Sure, they sometimes formed alliances to drag down an overwhelmingly dominant main heroine — but the moment that goal was achieved, they splintered again like the Warring States period, every ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠woman for herself.

"I am different from you. Mikhail loves me. You know that, don't you?"

"What?"

"I asked if you know him."

Arlea shook her head.

"He is mine. At least for now, he is my provisional consort."

Eyes curved like crescent moons pierced through me. In that satisfied smile, I saw a bold, unapologetic possessiveness.

My collarbone and sleeves were covered in the kiss marks Arlea had left behind. True to her yandere nature, her jealousy and ownership ran deep. Some of it had loosened a little — but still.

They may cooperate when necessary.

In the end, they would eliminate each other.

"…You came all this way just to say that."

Sophia crossed her arms and glared. Arlea shrugged.

"You and I both know — we aren't the only ones after Mikhail."

"Other bitches are scheming in the shadows, I'm sure."

Sophia muttered. If things continued like this, further conflict was inevitable. I could already see it coming.

"And… there's an axis of evil trying to kill everyone, too. Trying to take Mikhail. Is that really what you want?"

When Arlea said this, Sophia nodded as if in agreement.

"No. Absolutely not."

"Good. Remember that feeling. Incidentally, you arrived first and laid your groundwork. Thorough. Very thorough."

"That's right. I wanted to show Oppa a side of me he could be proud of when he arrived."

"I'm sure you did. But of this I am certain: I care for him and love him more than you."

"What?"

"Unlike you, who puts him under hypnosis. Unlike you, who uses him as a lab assistant and a test subject and takes pleasure in torturing him. We differ from the very essence."

"…Heh."

Sophia snorted as if the accusation were absurd, but she had no retort.

Aphrodisiacs. All manner of sexual experiments and brainwashing. Using those methods to conquer me — the protagonist — that was who Sophia was.