Outside Shixi Town, in a desolate, rarely visited forest.

Li Hai stood with his hands behind his back, observing the kind-faced old man before him, and sneered, “Zhou Yugen, Zhou Yugen, you look like a decent person, so why do you act so heinously?”

The old man, Zhou Yugen, looked at Li Hai in terror, forcing a smile as he asked, “Young hero, may I ask how I, Zhou, have offended you? You destroyed my garden, killed my subordinates, and finally abducted me to this desolate wilderness?”

Li Hai had no intention of answering; instead, he asked, “Zhou Yugen, do you still remember Qiu Fangzheng?”

“Qiu… Fangzheng?”

Zhou Yugen furrowed his white eyebrows, pondered for a long while, then gave a bitter laugh and said, “Young hero, please forgive this old man’s age and frailty; my mind has also deteriorated greatly, and I truly cannot recall.”

“Forgotten?”

Upon hearing this, Li Hai couldn't help but sneer coldly, “As I see it, you’ve harmed too many people, so you can’t remember, can you?”

“Uh, this… ha ha ha.” Zhou Yugen could only give a dry laugh.

Then Li Hai asked again, “If you can’t remember Qiu Fangzheng, then what about his younger sister, Qiu Fanglan? Still can’t remember?”

“Qiu Fanglan… Lan…”

Zhou Yugen recalled for a moment, then again gave a bitter laugh and said, “Young hero, to be honest, I truly can’t remember who this person named Qiu Fanglan is…”

“You’re lying.” Li Hai suddenly stated, “Your heart skipped a beat.”

With that, without waiting for Zhou Yugen to argue again, Li Hai kicked his leg.

Crack!

Bone and flesh burst, and blood splattered.

“Ah ah ah!”

Zhou Yugen screamed, then collapsed to the ground, clutching his broken leg with the stark white bone protruding.

“How about it?” Li Hai said unhurriedly, “Have you remembered yet?”

“I remember, I remember!” Zhou Yugen stammered through the intense pain, “Qiu Fanglan… I sold her.”

“Sold her?” Li Hai frowned, “To whom?”

“I sold her to a wealthy family.” Zhou Yugen stammered, “They… they needed a daughter, so…”

Before he could finish speaking, Li Hai kicked and broke his other leg.

“Ah ah ah ah!”

Zhou Yugen was so pained he nearly went mad, so he could no longer maintain his previous kind demeanor. He snarled at Li Hai, “You little beast, I’ve already answered you, why did you still cripple my legs?!”

“Your Qi 脈 is chaotic, and you’re full of lies.” Li Hai shook his head and sighed, “I’ve lost my patience with you.”

With that, he took out a hemp rope and a few knives from his Grotto-Heaven.

“It seems I’ll have to make you suffer a bit.”

Li Hai toyed with the sharp knife, looking at the terrified Zhou Yugen, and said coldly, “Then you’ll tell the truth.”

Subsequently, a show of lingering death, intertwined with blood and screams, slowly unfolded deep within the desolate forest.

And Zhou Yugen, as the ‘actor,’ finally began to reveal everything under the relentless cutting of the knives.

It was also from his words that Li Hai gradually understood what Qiu Fangzheng’s younger sister had endured.

After Qiu Fangzheng was killed that year, his younger sister, Qiu Fanglan, was eagerly abducted by Zhou Yugen back to his mansion.

And in the following three months, she was tortured to the point of being unrecognizable and nearly insane.

Because of this, Zhou Yugen quickly lost interest in Qiu Fanglan and resold her at a very low price to a group of human traffickers.

As for where these human traffickers later sold Qiu Fanglan, Zhou Yugen was not very clear.

He only learned from those human traffickers in later years that this woman, through constant wandering, seemed not to have lived past twenty.

Most likely, she had died.

“Truly a living beast.”

Li Hai shook his head and sighed, “Your entire family are beasts.”

Then, he turned the blade and chopped off Zhou Yugen’s head.

…

“My lord, you… mean… my younger sister…”

Deep within the 溶洞 of Yupan Mountain, Qiu Fangzheng stared blankly at Zhou Yugen’s head, then excitedly said, “Was… rescued… rescued?!”

“That’s right.” Li Hai nodded, affirming, “After you died that year, as soon as Qiu Fanglan was captured by this Zhou Yugen and brought into his mansion, she was rescued by a passing martial Dao expert.”

“Then, what happened after that?”

For some reason, Qiu Fangzheng’s speech suddenly became clear. He asked urgently, “My lord, Xiao Lan… what happened to Xiao Lan after that?”

“She’s doing well.”

Li Hai said, “According to my investigation, after Xiao Lan was rescued by that expert, within half a year she fell in love with and married the expert’s son, then left this Dragon Mountain and went to the Great Jing Dynasty in the north.”

“The Jing Dynasty is good, the Jing Dynasty’s territory is peaceful and stable.”

Qiu Fangzheng smiled, which was rare for him. “How to put it, it’s ultimately much better than Dragon Mountain.”

“If there are no accidents,” Li Hai continued, “your younger sister’s grandchildren should also be adults by now.”

“Yes.” Qiu Fangzheng said contentedly, “My father and mother, if they know in the underworld, should be able to rest in peace.”

Li Hai remained silent.

“My lord.” Qiu Fangzheng slowly stood up from the ground, “I will take you to that ancient sect ruin now.”

“Good.” Li Hai nodded and also stood up from the ground.

Then the two… no, the two ghosts transformed into two hazy phantoms and plunged into the pool, disappearing within this 溶洞.

…

After leaving the 溶洞, Li Hai closely followed Qiu Fangzheng, moving through layers of mountains, turning east and west, making his way deep into Yupan Mountain.

It was during this journey that he first learned… that the ghost’s ability to pass through objects was not without limits.

Although any ghost could easily pass through sealed rooms and thick rock walls, this ability to dematerialize and pass through solid objects could not be used indefinitely.

To put it simply, just as a person, no matter how long he holds his breath, must eventually breathe.

When a ghost passes through solid objects, there is a numerical limit to the thickness of the object it can pass through at one time; it cannot pass through indefinitely.

For example, the lowest-level Wraith-level ghosts have a maximum wall-penetration thickness of ten zhang.

If a wall’s thickness exceeds ten zhang, unless there are large cracks or holes within the wall, Wraith-level ghosts cannot penetrate it and can only linger outside.

As for the higher-level Fierce Soul-level ghosts, Li Hai discovered after testing that their wall-penetration thickness is about one hundred zhang.

This value is neither thin nor thick, somewhat in between.

If Li Hai were trapped in a deep underground cave where all directions (up, down, front, back, left, right) far exceeded one hundred zhang in thickness, he would only be able to stay imprisoned inside, with no chance of escape.

As for even higher-level ghosts, according to some information in the warehouse at the Demon Slayer Division’s outpost in Niujiao Town, they should be called 【Solid Ghosts】. The wall-penetration thickness of these Solid Ghost-level ghosts might reach a thousand zhang.

In other words, even a thousand zhang deep underground, a Solid Ghost could pass right through.

This level is considered very, very strong.

“My lord, that small path has been reached.”

In an unfamiliar 溶洞 deep within Yupan Mountain, Qiu Fangzheng pointed to a dark cave in the rock wall ahead and respectfully said to Li Hai, “Just follow this cave path all the way down, and at the end, you will reach the outer wall of the ancient sect ruin.”

Li Hai stared intently at the cave ahead and said in a deep voice, “Very well, let’s go.”

Then, the two ghosts transformed into black smoke and swiftly flew into the cave.