Beauty Meets Xianxia: Heart of Harmony

A Grimmer Xianxia — Six Fairy-Tale Maidens Reborn in the Dao

A stolen rose, a fractured cultivation path, and the Dao between opposites

Quick takeaway

Měi Xīn (美心), a mortal with an unremarkable spiritual root, enters the mountain palace of Yě Shòu (野兽 / 野獸) to settle her father’s karmic debt after he steals a spirit rose. What begins as captivity becomes an argument about cultivation itself: can opposing forces coexist without one erasing the other? Měi Xīn’s answer is the Dao of Harmony — and it belongs to her, not to the Beast.

By the time Měi Xīn’s father reached the mountain pass, three things had already gone wrong. His merchant caravan had lost two carts to a landslide. The surviving mule had bitten him. And the road home, which should have taken him east through the pine valleys, had vanished beneath a wall of white mist that no sensible road had any business containing.

He was not, in fairness, a cultivator. He was a silk merchant with a talent for bargaining, a poor sense of direction and three daughters who had each asked him to bring something home.

The eldest wanted coral hairpins. The second wanted a bolt of cloud brocade.   Měi Xīn, the youngest, had laughed when he asked. “If you see a flower growing where it has no business growing, bring me that.”

Her sisters called this affected simplicity. Her father called it inexpensive.

So when he stumbled through the white mist and found an entire palace abandoned beneath winter stars, he thought first of shelter, then of food, and only much later of the possibility that surviving the night might require more intelligence than he had so far demonstrated. The palace gates stood open.

No servants greeted him. No bells sounded. Yet lamps kindled as he entered, one after another, golden flames blooming down corridors of black wood and pale stone. A dining table appeared set for one. Hot rice steamed beside mushroom broth. A brazier glowed. Even the mule, when tethered in the outer courtyard, discovered a trough of warm water and immediately forgave the universe.  The merchant did what frightened mortals have always done in supernatural palaces. He accepted the hospitality and promised himself he would ask questions in the morning.

Morning arrived under a sky the colour of pearl. Beyond the eastern hall he found a garden enclosed in crystal walls. Every tree stood leafless except one.

At its centre grew a rose bush. One flower remained.  Its petals were white at the edges and deep crimson near the heart, as though winter and blood had negotiated a temporary truce. Frost clung to the stem. Beneath the soil, faint lines of light pulsed like meridians.  A flower growing where it had no business growing. The merchant sighed.

“Měi Xīn,” he muttered, “you are going to be the death of me.”

He reached through the low barrier and plucked the rose. The palace screamed.  Not metaphorically.  Every window shook. The lamps went black. The frozen garden cracked from wall to wall, and something enormous landed behind him with enough force to drive dust from the beams.

The merchant turned. The creature before him had the general shape of a man in the same way a thunderstorm has the general shape of weather.

He was tall, broad-shouldered and dressed in torn black robes embroidered with a faded mountain crest. One side of his face remained human: sharp cheekbone, dark eye, mouth drawn tight with fury. The other had warped beneath coarse black fur and ridged bone. Two horns swept backwards through long unbound hair. One hand ended in human fingers.

The other ended in claws. Red yang qi boiled from his body in violent waves.  Beneath it, something colder and darker barely moved. The merchant dropped the rose.  The creature looked at it. Then at him.

“You entered a sealed cultivation ground.”

The merchant swallowed. “Yes.”

“You ate from my table.”

“Yes.”

“You slept under my roof.”

“Yes.”

“And after receiving food, warmth and shelter, you tore the heart from the formation sustaining this estate.”

The merchant considered the rose lying between them. “When you put it like that, it does sound discourteous.”

The creature’s growl rattled the frost from the glass.

The Karmic Debt

The palace master called himself Yě Shòu. Whether that had once been his name, a title given by enemies, or merely an accurate description was unclear.

He did not kill the merchant. This was partly because the palace wards had recognised the man as a guest before he touched the rose. Killing a guest would create a second karmic imbalance while Yě Shòu was already struggling with the first.  It was also because murder would not restore what had been damaged. The rose was not decorative. It was the visible heart of a formation built through the entire mountain.

Each petal measured the balance between the two currents inside Yě Shòu’s body: raging yang and stagnant yin. When the currents moved in harmony, the flower held. When one dominated, a petal darkened and fell.  The merchant had not caused the curse. He had, however, removed the instrument regulating it.

A fine distinction, but an important one if you were the merchant. Yě Shòu repaired the stem with a line of qi. The flower reattached itself reluctantly, which seemed fair.

“The karmic seal marked you the moment you crossed the boundary,” he said. “Taking the rose completed the debt.”

“What do I owe?”

“Something equal to what you endangered.”

The merchant went pale. “My life?”

“That would be simple.”

There are few sentences more alarming than those words when spoken by a horned cultivator with one clawed hand. Yě Shòu’s gaze shifted to the merchant’s sleeve. A strand of crimson light had wound itself around the man’s wrist. Three finer threads stretched from it, trailing invisibly toward the Mortal Realm.

“Three daughters.”

The merchant stepped backwards. “No.”

“I did not ask for them.”

“You looked at the threads.”

“I have eyes.”

“One of them asked for the rose,” the merchant whispered.

The red thread brightened. Yě Shòu went still.  Karma, which has no tact whatsoever, had apparently decided this was relevant. The merchant covered his face.

“She asked for a flower. She did not ask me to trespass into a cursed palace and dismantle a cultivation formation.”

“For once,” Yě Shòu said, “we agree.”

He gave the merchant three days to leave. At the gate, the red seal burned against the man’s wrist.

“You may return yourself and settle the debt with your life,” Yě Shòu said. “Or the daughter connected to the rose may come willingly and enter the formation in your place. I will not drag her here. I will not accept her bound, drugged or deceived. Choice is part of the karmic exchange.”

The merchant stared at him. “And if neither of us returns?”

“Then the debt will recoil through your meridians until your body fails.”

“How long?”

Yě Shòu looked at the damaged rose. “Before the last petal falls.”

The merchant rode home carrying the flower he had stolen. Měi Xīn took one look at his face and said, “That is an impressively expensive rose.”

Her Father’s Life

Her sisters argued for three days. The eldest said their father should flee south.  The second suggested hiring cultivators. A cousin recommended burning the rose, which caused every lamp in the house to explode simultaneously and was therefore removed from future strategic discussions.

Měi Xīn listened. Her father grew weaker by the hour.  The karmic seal had spread from his wrist toward his heart. Crimson veins pulsed beneath the skin. Each time he tried to circulate breath, he coughed blood into a cloth and hid it badly.

“You are not going,” he told her.

“You were given two choices.”

“I choose the first.”

“To die.”

“Yes.”

“That is not a particularly inventive solution.”

He glared at her with the exhausted dignity of a parent discovering that his child has inherited his stubbornness but improved it. “I will not trade you for my life.”

“You are not trading me. I am choosing whether to enter a cultivation formation connected to a rose I requested.”

“You requested a flower.”

“And you apparently found the only one guarded by a cursed beast cultivator. Your gift-buying instincts have always lacked restraint.”

He almost laughed. That made the decision easier.

Měi Xīn had no spiritual root worth mentioning. At sixteen she had been tested by a travelling sect and informed, with great solemnity, that her meridians were “balanced but unremarkable”.  Her sisters had mourned the insult for weeks. Měi Xīn had gone home and finished repairing the household accounts. Balance, she had discovered, was only considered unremarkable by people who had never managed a family in debt.

She left before dawn. No prince came to stop her.  No immortal descended to offer a secret technique. Her father gave her a knife, three packets of dried plums and the practical advice that if the Beast tried to eat her, she should aim for the eyes.  It was not elegant. It was useful.

When Měi Xīn crossed the white mist, the karmic seal vanished from her father’s wrist. A matching mark appeared on hers.

Yě Shòu waited at the palace gate. “You came willingly?”

“No. I came resentfully. But I came by choice.”

The seal flashed once. Apparently karma accepted nuance.  Yě Shòu stepped aside. Měi Xīn entered the palace. The gates closed behind her.

The Palace of Withering Spring

The palace was not abandoned. It was wounded. Měi Xīn understood this before she understood anything about cultivation.

Doors opened a fraction too slowly. Lamps flared hot enough to scorch sleeves, then died into blue embers. In the western courtyard, spirit cranes paced in circles because the formation that guided their migration no longer knew where north was. A fox spirit had taken up residence in the library and hissed whenever anyone touched the medical texts.

The servants were not human but constructs of woven qi: paper attendants, bronze kitchen spirits, small stone beasts that carried coal between braziers. They functioned when the palace currents balanced and froze whenever Yě Shòu’s violent yang surged. Which was often.

On her first evening, a porcelain teapot launched itself across the dining hall. Měi Xīn caught it. Yě Shòu stared.

“Does that happen frequently?”

“No.”

The lid shot after it and struck him in the shoulder. Měi Xīn looked at the teapot. Then at him.

“I admire your confidence.”

He growled. Three lamps exploded.

The Withering Rose lost a petal. That was how she learned anger had consequences.

The rose now stood beneath a crystal dome in the centre of the inner court. Eight petals remained. Every time Yě Shòu’s yang qi overwhelmed the stagnant yin locked beneath it, another petal darkened.

“What happens when they are gone?” she asked.

“The formation collapses.”

“And you?”

“I stop being able to contain the transformation.”

“You become a beast.”

His jaw tightened. “I already am one.”

Měi Xīn studied him. “No. You are a man with horns being rude in a dining room.”

He stared at her for so long that a bronze serving spirit quietly backed away. Then, unexpectedly, he laughed.

It was a terrible sound. But it was laughter.

The Beast’s Cultivation

Yě Shòu had once been the brightest disciple of the Chìyáng Sect. Their doctrine was simple—or, more accurately, brutally simplified: yáng advanced; yīn yielded.

The sect treated fire as the conqueror of water, strength as superior to weakness, and action as superior to stillness. This was Chìyáng Sect ideology, not a tidy summary of classical Chinese thought: yīn and yáng are opposing but interdependent aspects of change, not a moral ranking in which one is simply meant to defeat the other. A cultivator of Chìyáng rose by refining the aggressive current and suppressing whatever impeded it.

Yě Shòu had been very good at this. Too good.  His natural constitution carried unusually strong yang and unusually deep yin. Rather than cultivate both, his masters bound the yin channels with seals and fed the yang until it became a weapon.

For years he won every tournament. Then his body began to change.  The yang qi, denied an opposing current, consumed muscle and bone. The suppressed yin stopped circulating entirely and hardened through his lower meridians like black ice.

His sect called it deviation. Their solution was more suppression.  When that failed, they called him corrupted. This was convenient. Sects often prefer moral explanations for injuries caused by their own teaching methods.

Yě Shòu fled before they could destroy his cultivation core “for the safety of the realm”. He reached the mountain palace of an old physician who understood dual constitutions. Together they built the rose formation as a temporary regulator.

The physician died before completing the cure. Yě Shòu remained.  Decades passed. His face changed.  His sect moved on. The rose kept count.

Měi Xīn listened to all of this while sorting medicinal roots in the physician’s abandoned workroom. “You were taught to conquer half of yourself.”

“I was taught to cultivate.”

“Those appear to have been the same thing.”

His claws scraped the table. “You know nothing about cultivation.”

“Correct.”

The answer stopped him. Měi Xīn tied another bundle.

“Which means I have no professional reputation to defend. Very freeing.”

The fox spirit in the doorway sneezed in what sounded suspiciously like agreement. Eight petals became seven.

The Problem with Obedience

Yě Shòu expected gratitude because he did not lock Měi Xīn in a tower, starve her or threaten her family. Měi Xīn considered the standard disappointingly low.

“You are here because of my karmic debt,” he told her. “The palace will protect you.”

“The palace threw a teapot at me.”

“It was a minor formation fluctuation.”

“The teapot was cast iron.”

“Porcelain.”

“That is not the reassuring part of the sentence.”

He gave her rooms overlooking the eastern garden. He supplied clothes, books and food. He forbade her to enter the lower cultivation chambers because his qi was unstable there.  Měi Xīn obeyed for four days. On the fifth she followed a trail of frozen spirit mice down the stairs. Yě Shòu found her kneeling beside an array carved into black stone.

“What are you doing?”

“Looking at the reason your palace keeps trying to kill the crockery.”

“Leave.”

“No.”

His yang qi rose so quickly the walls flushed red. Měi Xīn’s karmic seal burned.  The formation beneath her answered. For one terrifying moment, she felt his power enter the room like wildfire.  Every instinct told her to bow. Instead, she stood.

“Do not use qi to make me obey you.”

“I did not—”

“You did. Perhaps not deliberately. That does not make it less real.”

The red light trembled. Yě Shòu looked down at his clawed hand.  He had spent years telling himself the Beast was the fur, the horns, the teeth. Měi Xīn looked at the power filling the chamber.

“No,” she said quietly. “This is the part you should be afraid of.”

The yang collapsed. Not defeated. Released. Cold air rushed upward from the sealed channels beneath the floor. For the first time since she arrived, yin qi moved through the room.

The rose did not lose a petal. One darkened edge became white again.  Yě Shòu stared toward the courtyard. Měi Xīn exhaled.

“Well,” she said, “that seems worth investigating.”

The First Breath of Harmony

They began with the palace. Not with him.  Měi Xīn refused to become another physician trying to “cure” Yě Shòu while he remained a passive object of treatment. She also refused to become his devotional sacrifice, which disappointed several very old manuals in the library.

Instead, they repaired the circulation arrays. The palace had been designed around paired currents: geothermal yang rising through the mountain, glacial yin descending from snow-fed springs. Years of imbalance had left half the channels overworked and half almost dormant.

Měi Xīn could not manipulate qi. She could, however, notice patterns.  She mapped which rooms overheated before Yě Shòu’s temper rose. She watched which spirit beasts moved toward cold courtyards when the red current thickened. She compared the physician’s notes against the palace’s water clocks.

Then she began practising breathing exercises written for attendants with weak spiritual roots. Nothing happened for eleven days.

On the twelfth, she felt a thread of warmth move through her left palm and a thread of coolness through her right. She nearly shouted. Instead she sat very still, because shouting seemed unwise when discovering cultivation for the first time.  By evening she could hold both sensations without forcing either to disappear. Yě Shòu watched from the doorway.

“That is not a recognised technique.”

“It is breathing.”

“You are circulating two opposed currents.”

“I am breathing while inconveniently ambidextrous.”

He came closer. The moment his yang touched her small current, it tried to overwhelm it.  Měi Xīn slapped his wrist. He recoiled in astonishment.

“Do that again,” she said, “and I will cultivate violence.”

A sound escaped him that might have been a laugh. The rose held at seven petals.

Weeks passed. Měi Xīn’s cultivation grew slowly, irritatingly and without dramatic lightning.  She named the method Hé Xī — Harmonious Breath. Yě Shòu called the name simplistic.  She reminded him that his sect had named its foundational method Invincible Blazing Sun Dominates Ten Thousand Forces. He stopped criticising names.

The Last Petal

Harmony was not peace. This was the lesson they learned too late.

For months, Yě Shòu improved. The black ice in his yin channels began to melt. His beast form stabilised. One horn shortened; then grew back after an argument about medicinal wine.

The palace revived. Spirit cranes stopped pacing. The fox spirit permitted three people to enter the library without hissing, although one was a kitchen construct and therefore arguably did not count.

Měi Xīn cultivated. She also began to miss home.  That was when Yě Shòu became afraid. Fear looked very much like anger in a man trained to turn every vulnerable emotion into fire.

“You cannot leave yet.”

Měi Xīn folded a robe into her travel chest. “My father is well. The debt seal has faded. The formation is stable.”

“The rose still has three petals.”

“It had seven when I arrived.”

“If you go, the balance may fail.”

“Then learn to maintain it.”

His eyes flashed red. “You are part of the formation now.”

“No.”

“You carry its qi.”

“I carry my qi.”

“The palace responds to you.”

“That does not make me palace furniture.”

The doors slammed shut. Every window sealed.  The red current roared through the walls. Měi Xīn went very still.

Yě Shòu saw the fear on her face. And, for one dreadful breath, did nothing.  The Beast had never been the claws. It was the belief that fear gave him the right to command.

Měi Xīn’s voice shook. “Open the doors.”

“If you leave—”

“Open them.”

“I cannot lose—”

“You do not get to finish that sentence as though losing me is worse than imprisoning me.”

The first petal fell. Then the second.  The palace screamed.

Yě Shòu looked at the rose. One petal remained.

His yang qi had filled every passage. Beneath it, the newly awakened yin recoiled and froze.  The old pattern. Dominate.  Submit. Destroy one side to preserve the other.

Yě Shòu’s claws lengthened. His face warped.  The final transformation began. Měi Xīn could have fled if the doors opened.

Instead she walked toward him. Not because love demanded sacrifice. Because she was furious.

“You learned nothing.”

His roar shook the roof. “I learned that balance depends on you!”

“No. You learned to lean on me instead of crushing yourself. That is not the same thing.”

The last petal blackened. Yě Shòu dropped to his knees.

Bones shifted beneath his skin. Měi Xīn stepped into the formation circle.  His red qi struck her Harmonious Breath like a flood. Pain ripped through her meridians.

For one instant she understood why cultivators worshipped power. It would have been so easy to push back.  To seize the yin current. To force him down.  To become the stronger will and call it balance. Instead, Měi Xīn opened her hands.  She did not submit. She did not dominate.

She held her own centre. “Your yang is yours,” she said through clenched teeth. “Your yin is yours. Stop asking one to kill the other.”

Yě Shòu’s eyes found hers. The palace shook.  The final petal loosened. Then stopped.

Te Dao Between Opposites

Yě Shòu had spent his entire cultivation life trying to decide which half of himself deserved to win. In the end, neither did.

He opened the seals around his yin meridians. Not cautiously.  Completely. Cold qi surged upward with enough force to crack the floor.

 The yang descended. The two currents collided at his heart.   For a heartbeat, Měi Xīn thought he had killed himself. Then the currents turned.  Not one around the other. Together.  Fire became motion. Water became depth. His yáng ceased being a weapon. His yīn ceased being a prison.

The beast form convulsed. Fur receded from one arm and spread across the other. One horn dissolved. The second remained, smaller and curved like dark jade. His claws shortened but did not vanish. The human half of his face changed too, losing the strained perfection of the disciple he had once been.

He did not become the man he had been before. That man had been sick.  He became something else. Something integrated.

The final rose petal lifted from the stem. Měi Xīn gasped.  Instead of falling, it divided into two. One crimson.  One white. Both remained.

Then Heaven noticed. Clouds gathered over the mountain. Yě Shòu looked upward.

“Oh,” Měi Xīn said.

He glanced at her. “What?”

“I believe you are about to be struck by lightning.”

The first bolt shattered the crystal roof. He laughed.  This time it sounded almost human. Almost.

He walked into the courtyard and raised both hands. Tribulation lightning descended.  Yang answered. Yin answered. Neither suppressed the other.

When the final bolt faded, Yě Shòu remained standing in the snow, smoking gently. Měi Xīn leaned against a pillar.

“You look terrible.”

“I have just crossed a cultivation boundary.”

“Yes. Very untidy.”

He smiled. The palace doors opened. By themselves.

What Beauty Chose

The karmic seal vanished from Měi Xīn’s wrist that night. She was free.  Yě Shòu did not ask her to stay. That mattered more than an apology.

At dawn, he carried her travel chest to the gate. The gesture would have been romantic if the chest had not contained four cultivation manuals, two medicinal kettles, several stolen library notes and enough dried plums to survive a minor siege.

“You are taking my physician’s commentary.”

“I annotated it.”

“That does not make it yours.”

“It was wrong in three places.”

He considered this. “Take it.”

The white mist parted. Měi Xīn looked back at the palace that had been prison, school, battleground and home in different proportions.

“What will you do?”

“Rebuild the lower arrays.”

“Without imprisoning anyone?”

“I have recently received extensive criticism of the practice.”

“Good.”

“And you?”

Měi Xīn tightened the straps on her pack. “Cultivate.”

“Where?”

“Everywhere.”

She had begun as a mortal girl with an unremarkable balanced constitution. Now the two currents inside her moved like matched threads.   Not powerful. Not yet. But hers.

Years later, cultivators would call her Měi Xīn, Heart of Harmony, founder of a path that taught paired forces without hierarchy. Her students learned that yin was not weakness.

Yang was not domination. Stillness was not surrender. Action was not conquest. They learned that harmony was not the absence of conflict, but the ability to remain whole while opposing truths moved through the same body.

Some students found this profound. Others complained that it was much harder than simply hitting things.

Měi Xīn agreed. In the years that followed, Yě Shòu visited sometimes.  He never returned entirely to human form. He stopped wanting to.

The horn remained. So did one line of dark fur along his forearm and the eyes that flashed red when he was angry. He learned to be angry without making the room obey him.

Měi Xīn learned that balance did not require never choosing sides. Sometimes injustice was quite clearly on one side and a sword belonged on the other.

They cared for one another. Whether they became lovers depended on which disciple told the story.

The oldest records are frustratingly unhelpful. They contain cultivation diagrams, correspondence about medicinal ratios and one note from Yě Shòu complaining that Měi Xīn had once again returned a borrowed text with corrections in the margins.

There is no wedding record. There does not need to be.

The Withering Rose remained in the mountain palace beneath its crystal dome. It never returned to one colour.  Half its petals grew crimson. Half grew white.  And when young cultivators asked Měi Xīn which colour represented love, she told them they had missed the point. The rose had never measured romance.

It measured whether one force was trying to erase the other. That was why it had withered. That was why it bloomed again.  And that was the heart of harmony.

From Beauty and the Beast to Xianxia

The bones of the old fairy tale are still visible here: a father takes a rose that is not his, a daughter enters the Beast’s domain in his place, an enchanted household watches the consequences, and the Beast’s future is tied to a flower. But Heart of Harmony changes what the rose is measuring. It is not waiting for Měi Xīn to fall in love with Yě Shòu. It is measuring whether his cultivation can survive a system built on domination.

That matters because the problem is larger than his appearance. Yě Shòu has been taught to treat one part of himself as strength and the other as weakness, then to cultivate accordingly. The Beast is therefore not cured by becoming conventionally handsome, nor by being rewarded with a woman who loves him enough. He has to stop treating power as the right to make everything else yield.

Měi Xīn’s role changes with it. She arrives because of a karmic debt, but she does not remain a hostage, a devotional sacrifice, or an unpaid rehabilitation programme for an angry man with horns. She observes, experiments, cultivates, argues, leaves when she is free to leave, and eventually creates a path that is hers. Whether she and Yě Shòu later become lovers is deliberately left unresolved. Her achievement does not depend on the answer.

A Cultural Note on Yīn and Yáng

The Chìyáng Sect’s doctrine is intentionally distorted. Its elders turn yīn and yáng into a hierarchy in which yáng must dominate and yīn must submit. That serves the story, but it is not intended as a summary of Chinese philosophy.

Across Chinese philosophical traditions, yīn and yáng have often been understood as contrasting, interdependent and cyclical aspects of change. Different historical thinkers interpreted and ranked them differently, and some traditions did attach social hierarchies to the pair. Heart of Harmony borrows the language of complementarity for a fictional cultivation system rather than claiming to reproduce a historical Daoist practice.

Xianxia Terms in This Story

Měi Xīn — 美心 — “beautiful heart”; the heroine who develops the Harmonious Breath method.

Yě Shòu — 野兽 / 野獸 — “wild beast”; the cursed cultivator whose divided cultivation drives the palace formation.

Hé Xī — 和息 — “Harmonious Breath”; Měi Xīn’s fictional paired-current cultivation method.

yīn — 阴 / 陰 — one pole in the yīn–yáng relationship; associated in different contexts with qualities such as shade, receptivity, coolness and contraction.

yáng — 阳 / 陽 — the complementary pole; associated in different contexts with qualities such as sunlight, activity, warmth and expansion.

qì — 气 / 氣 — breath, vital material energy or vital force; in xianxia, commonly fictionalised as cultivatable spiritual energy.

dào — 道 — way, path or course; in xianxia, often used for the cultivated path or principle through which a character understands and transforms the world.

FAQ

How is Heart of Harmony still Beauty and the Beast?

The stolen rose, the father’s trespass, the daughter entering the Beast’s domain, the enchanted household and the Beast’s transformation all remain. The difference is that the central test is no longer whether Beauty can love the Beast enough to save him. It is whether both characters can act without possession becoming the price of attachment.

Does Měi Xīn fall in love with Yě Shòu?

Possibly. The surviving records are, very conveniently, useless on the subject. Their later affection is clear; whether it becomes romantic is deliberately left open because Měi Xīn’s cultivation path does not require a wedding certificate for validation.

Why does Yě Shòu remain partly beastlike?

Because integration is not restoration. His healed form is not the body he had before his cultivation broke down. The remaining horn, fur and altered eyes mark what he has lived through rather than defects that must be erased.

Is the Dao of Harmony a historical Chinese cultivation practice?

No. Hé Xī and Měi Xīn’s Dao of Harmony are fictional xianxia inventions. They draw on the broad literary usefulness of yīn–yáng complementarity, but they are not presented as historical Daoist techniques.

Why is the romance ambiguous?

Because this series is interested in what fairy-tale women do when romance is allowed to be part of a life rather than the purpose of it. Měi Xīn can love, leave, cultivate, found a lineage and argue in the margins of medical texts. One of these activities is not automatically more important than the others.