I've rewritten it as a smoother BTTH-style story scene while keeping your plot changes (Xiao Feng, Zi Yan, Xiao Yi Xian, awakened Woeful Poison Body, etc.):
A few days later, Zi Yan returned to the Fire Faction once again.
This time, however, she was carrying a large pile of high-grade medicinal herbs and rare spiritual plants.
The moment she found Xiao Feng, she dumped everything onto a table.
The mountain of medicinal ingredients instantly filled the room with rich spiritual energy.
Xiao Feng glanced over them and immediately recognized several rare ingredients that were difficult to find even in the Black-Corner Region.
"You found all of these?" he asked.
Zi Yan proudly raised her chin.
"Of course."
"I'm a treasure-hunting genius."
"Besides, I need more pills."
She sat down carelessly before continuing.
"My cultivation speed is already very fast. As long as I have enough high-energy pills, I can continue sleeping and digesting them."
"If I can reach the Sixth-Star Dou Huang and then break into the Seventh-Star Dou Huang realm, I can take the Mighty Huang Pill."
"The moment I succeed, I can quickly reach the peak of the Dou Huang class."
Xiao Feng nodded.
With her Ancient Void Dragon bloodline, such a cultivation method was indeed normal.
Furthermore, the medicinal pills he refined were all of the highest quality. Many even possessed pill patterns, making them nearly perfect.
There was no need to worry about unstable foundations or impure Dou Qi.
After checking the herbs, Xiao Feng stored them away.
"I'll refine them when I have time."
Zi Yan immediately smiled.
"Good."
"Then I'll go find more treasures."
Before Xiao Feng could say anything else, she had already disappeared from the courtyard.
Watching her leave, he could only shake his head helplessly.
That girl truly couldn't stay still.
After Zi Yan left, Xiao Feng suddenly noticed something.
Everyone had visited him recently.
Qing Lin had come.
Zi Yan had come.
Even messages from Xiao Yu and the others had arrived.
Only Xiao Yi Xian had not appeared.
A faint feeling of concern rose in his heart.
Without hesitation, he headed toward the secluded residence he had specially prepared for her.
The small palace was located far away from crowded areas.
It had been built specifically as a precaution.
If the Woeful Poison Body released poisonous mist during cultivation or sleep, it would not affect anyone else.
As Xiao Feng and Qing Lin approached the residence—
Suddenly—
BOOM!
A terrifying wave of energy erupted from the palace.
Purple poisonous mist surged into the sky like a volcanic eruption.
The poisonous clouds covered the entire roof before rapidly spreading outward.
The expressions of both Xiao Feng and Qing Lin changed.
"Not good."
Xiao Feng immediately turned toward Qing Lin.
"Qing Lin, stay here."
"Do not come any closer."
Before Qing Lin could reply, Xiao Feng vanished.
The next moment, he appeared directly inside the palace.
The entire room was filled with dense poisonous energy.
Yet Xiao Feng ignored it all and rushed into the bedroom.
The scene before him caused his heart to tighten.
On the large bed, a blanket was tightly wrapped around a trembling figure.
The moment she sensed his arrival, a familiar voice sounded from beneath the covers.
"Don't come closer..."
"I... I've become ugly..."
Her voice trembled slightly.
Xiao Feng immediately recognized it.
It was Xiao Yi Xian.
He slowly walked toward the bed.
"No matter what you become, I'll still like you."
His voice was calm and gentle.
The figure beneath the blanket shook slightly.
However, she remained silent.
Only faint sobbing could be heard.
Xiao Feng carefully reached forward and lifted the blanket.
The moment it fell away—
He froze.
A waterfall of beautiful snow-white hair flowed across the bed.
Every strand shimmered like moonlight.
Beneath the white hair was Xiao Yi Xian's tear-stained face.
Her eyes had changed as well.
The black pupils she once possessed had become a beautiful purple color.
The transformation made her look even more mysterious and ethereal than before.
Xiao Yi Xian lowered her head.
"My hair became white..."
"My eyes changed too..."
"I don't look normal anymore."
"I'm no longer worthy of standing beside you..."
Hearing those words, Xiao Feng felt both helpless and heartbroken.
He knew exactly why this had happened.
Previously, because of the special medicinal pill he had refined, containing both Fire and Wood attributes, the awakening of her Woeful Poison Body had been partially stabilized.
The visible changes had been delayed.
Now that she had successfully broken through to the Dou King realm, the suppression could no longer completely hide the effects of her physique.
The changes had finally manifested.
But to Xiao Feng—
This was never something ugly.
Instead, she looked more beautiful than ever.
He gently wiped away the tears on her face.
"Who told you this is ugly?"
Xiao Yi Xian blinked.
Xiao Feng smiled softly.
"Your skin is fairer than before."
"Your white hair looks like snow."
"And those purple eyes are beautiful."
"You look like an immortal fairy who stepped out of a painting."
"In fact..."
He paused.
"I think you're even more beautiful now."
Xiao Yi Xian stared at him blankly.
"Really?"
Xiao Feng nodded without hesitation.
"Really."
"I've never lied to you."
He then gently lifted her into his arms.
Walking toward the mirror nearby, he placed her before it.
"Look."
The reflection appeared.
A girl with snow-white hair stood before the mirror.
Her elegant appearance seemed untouched by mortal dust.
Her purple eyes carried a mysterious charm.
She looked less like an ordinary human and more like a fairy descended from the heavens.
For a moment, even Xiao Yi Xian herself became stunned.
Xiao Feng stepped behind her.
He wrapped his arms around her waist and rested his chin lightly upon her shoulder.
His voice became soft.
"No matter what happens."
"No matter what your Woeful Poison Body becomes."
"You'll always be Xiao Yi Xian."
"And you'll always be important to me."
The last traces of fear inside Xiao Yi Xian's heart finally disappeared.
The tears in her eyes slowly faded.
A beautiful smile bloomed across her face.
She gently leaned backward into Xiao Feng's embrace.
"It's so good..."
"...to have you beside me."
For the first time since her breakthrough, she felt completely at peace.
Xiao Feng gently brushed aside a strand of Xiao Yi Xian's snow-white hair before suddenly asking,
"Yi Xian, have you been taking high-grade poisonous medicines lately?"
The moment the words left his mouth, Xiao Yi Xian's expression became slightly guilty.
Xiao Feng immediately knew his guess was correct.
The sudden eruption of her Woeful Poison Body was simply too abnormal.
When he first met her, she was only a small Dou Disciple.
Now, in just over two years, she had already reached the level of a Three-Star Dou King.
Even Xiao Feng couldn't help feeling shocked by such cultivation speed.
It was practically like a rocket soaring into the sky.
In the original development of events, Xiao Yi Xian's strength should have increased rapidly only after she established her own Poison Sect and gained access to countless poisonous herbs and medicinal resources.
Yet now, her growth had happened years ahead of schedule.
Although the poisonous pills and resources he provided had helped greatly, according to his calculations, they should not have caused such an explosive increase.
There was only one possibility.
She had secretly increased her dosage.
Sure enough, Xiao Yi Xian lowered her head slightly.
"I..."
"I couldn't help it."
Her voice was soft and somewhat weak.
"I wanted to become stronger faster."
"I didn't want to always stand behind you."
"I wanted to help you too."
Hearing her explanation, Xiao Feng could only sigh helplessly.
For ordinary people, poison was something to fear.
But for someone with the Woeful Poison Body, poison was cultivation itself.
The stronger the poison, the faster her cultivation advanced.
To Xiao Yi Xian, those poisonous medicines were like an irresistible temptation.
Fortunately, she still possessed enough self-control to stop herself from going too far.
Otherwise, the consequences could have been disastrous.
Xiao Feng gently flicked her forehead.
"Little fool."
Xiao Yi Xian immediately rubbed her forehead and looked at him pitifully.
"I'm not blaming you."
His voice softened.
"But you need to be more careful."
"The Woeful Poison Body is powerful, but it isn't something you can recklessly push forward without consequences."
"If something happened to you, what would I do?"
Hearing those words, Xiao Yi Xian's eyes immediately softened.
The warmth in her heart spread throughout her body.
She quietly nodded.
"I understand."
Seeing her obedient appearance, Xiao Feng smiled.
"Good."
"Now that you've reached the Dou King realm, I can finally begin helping you properly control your Woeful Poison Body."
"Once we succeed, your future cultivation speed will become even more terrifying."
"And more importantly, you'll no longer need to constantly worry about accidentally harming the people around you."
Xiao Yi Xian's beautiful purple eyes immediately brightened.
"Really?"
"Really."
Xiao Feng nodded confidently.
"As long as I'm here, we'll definitely find a solution."
The anxiety that had troubled her since awakening her physique finally disappeared completely.
Without thinking, Xiao Yi Xian stepped closer and lightly hugged his arm.
A bright smile appeared on her face.
Xiao Feng smiled and gently kissed her forehead.
"Now stop worrying."
"Qing Lin is still waiting outside."
"If we stay in here any longer, she'll probably think something happened."
Hearing Qing Lin's name, Xiao Yi Xian immediately laughed.
That little girl had undoubtedly been worried sick.
Without waiting for her response, Xiao Feng directly lifted Xiao Yi Xian into his arms.
"Ah!"
Xiao Yi Xian let out a surprised cry.
Her face immediately turned slightly red.
"Xiao Feng!"
"What?"
"Put me down."
"No."
"Why?"
"Because I feel like carrying you."
Seeing his shameless expression, Xiao Yi Xian could only helplessly hide her face against his shoulder.
A few moments later, the two emerged from the palace.
Outside, Qing Lin was anxiously pacing back and forth.
The moment she saw them, her eyes lit up.
"Brother Xiao Feng!"
"Big Sister Yi Xian!"
"You're finally out!"
She immediately rushed over.
Seeing both of them safe and unharmed, she finally let out a long sigh of relief.
Then her attention instantly shifted.
Her emerald-green eyes widened.
"Big Sister Yi Xian!"
"Your hair!"
"It's so beautiful!"
Qing Lin immediately ran around Xiao Yi Xian like a curious little bird.
She couldn't stop staring at the beautiful snow-white hair flowing down her back.
Combined with her fair skin and purple-gray eyes, Xiao Yi Xian now possessed a unique beauty unlike anyone else.
Qing Lin's eyes sparkled.
"It looks amazing!"
"You look like a fairy!"
The sincere praise immediately made Xiao Yi Xian smile.
"Really?"
"Of course!"
Qing Lin nodded repeatedly.
"I've never seen anyone this beautiful before."
The two girls quickly began chatting together.
One was dressed in white with snow-white hair and purple eyes.
The other possessed emerald-green hair and jewel-like green eyes.
Their appearances were equally unique.
Watching the two of them laugh and whisper together, Xiao Feng quietly walked toward a nearby pavilion.
A cup of tea soon appeared in his hand.
Sitting there peacefully, he looked at Xiao Yi Xian and Qing Lin.
One possessed snow-white hair and purple-gray eyes.
The other had emerald-green hair and beautiful green pupils.
Both were girls with extraordinary destinies.
Both had followed him through countless hardships.
Looking at them, a faint smile appeared on Xiao Feng's face.
Interpreting their conversation, Xiao Feng finally revealed one of the pieces of information he had been investigating for quite some time.
"I may have found a clue related to a Strange Flame."
The moment those words left his mouth, both Xiao Yi Xian and Qing Lin immediately turned their attention toward him.
"A Strange Flame?" Xiao Yi Xian asked, her purple eyes widening slightly.
Xiao Feng nodded.
"Among the Strange Flames listed on the Heavenly Flame Ranking, there is one called the Ghostly Poison Flame, ranked twentieth."
"I've been gathering information from various sources in the Black-Corner Region. Whenever I encountered poison masters, poison swamps, ancient records, or places with unusually dense poison Dou Qi, I made sure to investigate them."
Hearing this, Xiao Yi Xian became increasingly attentive.
"For the past few months, I discovered several suspicious locations. Unfortunately, most of them are located in the southern and eastern regions of the continent. They are too far away for us to immediately verify."
Xiao Feng paused before continuing.
"However, during my investigation, I repeatedly came across records related to the Poison Swamps of the Izumo Empire."
"The records mention that once every four years, an enormous amount of poison energy gathers in a specific region of the swamps. For nearly a month, the concentration of poison Dou Qi becomes several times denser than normal before gradually dispersing again."
Qing Lin blinked.
"That sounds very unusual."
Xiao Feng nodded.
"Exactly."
"Natural phenomena don't normally repeat with such regularity."
"The last occurrence happened about one year ago."
"Which means the next cycle will arrive in approximately three years."
The more Xiao Yi Xian listened, the brighter her eyes became.
As someone possessing the Calamity Poison Body, she understood better than anyone how unusual such a location was.
A place capable of gathering such an enormous amount of poison energy might very well be connected to the Ghostly Poison Flame.
If she could obtain that Strange Flame, controlling her poison body would become significantly easier.
For the first time since the topic began, genuine hope appeared in her eyes.
"Do you really think it could be there?" she asked softly.
"I can't guarantee it," Xiao Feng answered honestly.
"But I believe the possibility is quite high."
As he spoke, he took out an ancient map from his storage ring.
The map looked worn and weathered, clearly having existed for many years.
"I found this inside the storage ring of a deceased expert during one of my expeditions."
"The map contains several markings related to poisonous lands and hidden locations."
"The most interesting part is that the final marked location coincides with the territory of the Izumo Empire."
Xiao Yi Xian immediately accepted the map.
She carefully spread it open on the table before taking out a modern regional map for comparison.
The room quickly became silent.
Several minutes passed.
Her eyes grew wider and wider.
The routes...
The mountain ranges...
The rivers...
The locations matched surprisingly well.
Finally, Xiao Yi Xian raised her head.
There was excitement she could no longer hide.
"The locations really match!"
"The marked area is actually inside the Izumo Empire!"
Seeing her reaction, Qing Lin also became excited.
"So there really might be a Strange Flame there?"
"Possibly," Xiao Feng replied with a smile.
"I'd say there's at least a seventy percent chance."
The moment she heard that estimate, Xiao Yi Xian could no longer contain her emotions.
For years, the Calamity Poison Body had been a shadow hanging over her future.
Now, there was finally a path toward controlling it.
Before Xiao Feng could react, Xiao Yi Xian suddenly stepped forward and threw herself into his arms.
"Xiao Feng!"
She hugged him tightly.
A bright smile bloomed on her face.
"Thank you!"
"Thank you so much!"
In her excitement, she repeatedly kissed his cheeks while expressing her gratitude.
Caught off guard, Xiao Feng could only laugh helplessly.
"Alright, alright."
"I haven't even confirmed it yet."
"But if the Ghostly Poison Flame is truly there, then no matter what, I'll help you obtain it."
Xiao Yi Xian nodded vigorously.
Her snow-white hair swayed behind her as she smiled.
"Mn!"
"I believe you."
Beside them, Qing Lin covered her mouth and giggled.
"It seems Little Fairy Doctor Sister is happier than she's been in a very long time."
Xiao Yi Xian's face turned slightly red, but she didn't let go of Xiao Feng's arm.
For her, this wasn't merely news about a Strange Flame.
It was hope.
Hope that one day she could fully control the Calamity Poison Body, stand proudly beside the people she cared about, and no longer fear hurting those around her.
And for that possibility, she was sincerely grateful to Xiao Feng.