Yin-Yang Refinement: Birth of the Moon's Messenger

Wiping away the cold sweat trickling down his face, Choi Siwoo dismissed all the disorienting message windows cluttering his vision.

"Kay. Let's get started."

"Good. Buy it."

"It's fine."

He'd earned a substantial amount of points, including from this latest incident. When it was time to spend big, he had to go all in.

Tsk... Fucking expensive.

His points, which had exceeded 600,000, had vanished in an instant. Buying the Fire Heart Flower, Cold Ice Snow Flower, and now this recipe—it was enough to bend his back.

He'd be lying if he said it didn't sting.

'Gotta think of it as a necessary investment.'

What he was about to do was crucial for his future plans.

In Choi Siwoo's hand after purchasing the recipe was a scroll faintly glowing with light. It was filled with complex ancient script that no one could decipher.

'Let's see...'

Unrolling it revealed a large diagram the size of a rug. At the center was a massive circle representing yang and yin energies.

Without hesitation, he placed the Fire Heart Flower and Cold Ice Snow Flower on it.

"Hoo..."

Crossing his legs in a meditative pose, a blue mana glow began circulating through his meridians.

Woooong—!

Strange patterns engraved themselves around Choi Siwoo. The scroll voraciously devoured mana at a steady yet rapid pace, unfolding its unique alchemy formation and emitting an ominous hum.

"Kuhk..."

Cold sweat beaded on his forehead. It sucked in even the power stored in his dantian like a fussy brat.

A stinging sensation came with a rapid influx of mana, only for it to drain out again in a cycle.

How many minutes passed? As Choi Siwoo steadied his breathing, the two flowers vanished from before his eyes, replaced by a sinister purple pill exuding an otherworldly aura.

Astoundingly, the pill floated mid-air on its own, demonstrating the profound principle of void attraction.

Grinning broadly, Choi Siwoo carefully picked up the pill. Its crystalline sheen drew an involuntary gasp of admiration.

"This is the Yin-Yang Pill..."

The fist-sized purple elixir looked like a cheap orb on the outside, but opposing energies churned wildly within.

'A miraculous pill only immortals who achieved corporeal transcendence could consume.'

He wasn't sure if it was accurate—just what was passed down. When he'd first heard the description in his previous life, he'd thought it was exaggerated, but seeing it now, he understood it wasn't hype.

Crrrack!

Gripping the Yin-Yang Pill in his hand shook the entire space. Absurd that a mere spiritual pill could affect its surroundings like this.

'Time to start.'

A faint divine power spread from Choi Siwoo, declaring a small domain barely large enough for one person.

A holy technique he'd obtained from Yurika, limiting recovery enhancement and repelling evil energies to a specific area. Chosen carefully to avoid harming her.

To that, he shoved a special drug made by Jeon Eunbyeol into his mouth.

"......"

Enduring the brutally ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠bitter taste synergized with Sacred Territory Declaration, maximizing the drug's effect.

"Kay. I'll hold back, but if I seem like I'm falling into qi deviation, I leave it to you."

Taking a deep breath, Choi Siwoo swallowed the Yin-Yang Pill down his throat.

Despite its fist-sized bulk, it melted on his tongue like cotton candy soaked in water.

"......"

A brief moment passed.

Thump—!

"Ugh!"

A pounding heartbeat rocked his body like it would explode.

"Kuhk!"

Flames spewed from his open mouth. Heat scorched his esophagus and internals.

Biting his lip, he circulated his energy everywhere. His lower dantian throbbed.

Vast yang energy battered it, causing excruciating pain.

'Even with senses blocked, it hurts this much...'

He now understood why only enlightened immortals who transcended the mortal coil could endure it.

Sensation fled his fingertips as bone-chilling cold surged in. Fresh blood from his nails froze into icicles.

The yin energy flowed to the heat-filled lower dantian, where they met and began mixing.

Opposing forces clashed for dominance.

"Urgh!"

Swallowing his groans, Choi Siwoo cursed inwardly up a storm.

In his dantian, yin and yang raged like they owned the place, samba dancing wildly.

Coaxing and soothing. Matching Kay's signals, he circulated and harmonized the energies.

"Kuh... Aaaagh!!"

His body burned and froze in cycles.

Crack—!

Skin split and rotted away with a sound, only for new flesh to sprout, forging even stronger vitality.

His jet-black hair, symbol of youth, bleached white, crumbled, regrew, and repeated.

Amid this hellish ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠ordeal, Choi Siwoo never lost his mind. Biting his tongue to quench thirst with his own blood.

He recalled why he'd made and consumed the unplanned Yin-Yang Pill.

'I need to get stronger.'

His regressed life had been one of sacrifice and resignation. Countless beings had pinned hopes on him, only to fade.

His back and underfoot crawled with the resentful dead who failed to achieve their goals.

In this life, he had to repay that faith.

'No, I don't even need such grand reasons.'

The cries of a child he couldn't protect ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠or even see echoed like hallucinations. He didn't want to lose anymore. Didn't want to let go.

That was all.

Silently enduring. ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠His preset alarm rang perfectly on time.

"Hoo, Kay... Turn on the broadcast."

Beep. The screen in his private chamber lit up.

The announcer screamed desperately at the red-tinged gate.

Chaos everywhere. Understandable. If that gate broke out, it wouldn't end with "a lot of people died."

'Yeah... if it fails.'

On the phone screen beside him, Namgung Mir-related stocks plummeted rapidly.

A smile crept across his face amid the pain. Everything was going as planned.

'Unsure if regression is real...'

But major events hadn't changed at all. Choi Siwoo had bet on that, with sweet rewards within reach.

"Kay! Now!"

Perfectly timed, maximum shares acquired.

'...That settles Mir.'

Now, just endure the raging energies within silently.

* * *

"......"

Hellish time passed.

Forcing open trembling eyelids, the wildly bucking energies had miraculously calmed.

Around the floor where he'd sat, bodily fluids reeking of copper scattered.

Charred dead skin and crumbling bone fragments lay there.

'Shedding bones and exchanging marrow...'

Not the proper enlightenment way with floating and flashy lights, but close enough.

Choi Siwoo chuckled, knowing Jeon Eunbyeol would chew him out, then stood calmly.

He noticed his eye level had changed.

'Grew taller...'

Mirror check: Height from mid-170s cm to early 180s cm. Scars gone completely. Skin baby-smooth too, but...

'Better looks are a bonus.'

Most important: his dantian. Split into two lower dantians, each holding opposing energies in circulation.

Truly yin and yang divided. A miraculous impossibility for normal structures. He smiled deeply.

"Success."

Originally, the Yin-Yang Pill was the first elixir absorbed by a hero titled Muguk Wicheon in his previous life.

Curious how he handled opposing forces with abnormal mana reserves, he'd asked once...

Thanks to that, Choi Siwoo could reclaim—and surpass—his old realms faster.

"Nice."

The ashen-faced announcer now shouted in a different tone. The red gate shifted to white—the mark of conquest.

Soon, the weary assault team emerged.

His phone alarms blared wildly. Ignoring them, he stared intently at the gray long-haired woman on screen.

"...Kay. Send the prepared email to Mir. Tell Jeon Eunbyeol it's time to start."

Choi Siwoo closed his eyes, thinking.

Finally... the gears to change that regret-filled future had begun to turn.

* * *

Days later. Inside Prunel Academy's A-Class classroom.

"......"

Choi Siwoo inwardly cringed under the scorching gazes from all directions.

An unfamiliar female student approached him.

Twisting her body like a braid, she shyly opened her mouth.

"Um..."

"Fuck off!"

"U-Um..."

"Fuck off!!!"

"O-Oh, free after class today?"

Fuck! Pale-faced, Choi Siwoo glared at the deaf-as-a-post girls ignoring him completely.