A/N: I just confirmed it from the canon, and the battle for the supremacy would start after three years when Fei Cai is 13.

***

Fei Cai's request was immature and impudent, granted he was only 10-years-old, Fei Qing felt a need to discipline such a character. Greed affected the human mind negatively, and to correct his only son's mentality was his responsibility.

"Cai'er," Fei Qing began with a deep tone, "Greed is a slippery slope that one should never tread upon. Like I stated, choose one, and the others will be given to you based on your contributions."

Fei Qing observed his son's expression, and seeing his collected gaze, he couldn't help but speak once again, "Cai'er, next time, I won't be warning you." Fei Qing's tone contained a fit of gruff anger that any parent could mobilize for their child in a moment's notice. Feeling the impatience within his honest father's tone, Fei Cai shook his head, "Father, I am willing to pay for the Gu worm with my stipend."

His words made Fei Qing frown and feeling a little interested in the initiative from his son's side, Fei Qing toned down a bit and commanded, "Continue."

Fei Cai nodded. In his past life, though ordinary, he was ruthless to himself. He felt exhilarated by the concept of how a few laws could make a group of men mighty and the general populace helpless. Just mere words scribbled upon books bonded humans in the most inhumane manner, and Fei Cai loved that discovery. And, only when he thought that there couldn't be a form of power more open and honest, one fortunate accident ended his miserable life dedicated to pursuing wealth and brought him to this world where might made man.

His gaze condensed, and he pointed at the two Gu worms. The first one was the Wolf Strenght Gu. Meanwhile, the other Gu worm Fei Cai pointed at was one of the most coveted treasures of the Tribe— Rank 1 Aperture Nurture Gu Worm.

"Father, I want to exchange the Wolf Strength Gu and the Aperture Nurture Gu with my future stipends until I gain enough merits."

His words finally doused Fei Qing's anger with amusement. At least, his son didn't tread down the path of a harebrained once again and proposed a method that gave the deal its intended fairness. Fei Qing stroked his hairy chin and stated with a tone that made Fei Cai realize that negotiations were off the tables.

"You will be allowed to take the two Gu Worms only if the stipend acts an interest until you achieve the intended amount of contributions. Needless, to say, I will be the one to personally decide if your actions have redeemed the Gu worms or not."

The Tribe system of the Northern Plains was reasonably straightforward. Aside from a few ancestral rules, Tribe Chieftains words held absolute command until a younger Gu Master overthrew the previous Chieftain and take the crown for himself. 

Fei Cai showed a troubled expression, allowing Fei Qing to understand that his son wasn't freakishly uncanny but merely smart enough to finally speak up to him. This eased Fei Qing by a significant margin and allowed him to finally agree on the matter. The Aperture Nurture Gu was in the shape of a palm-sized furry brown spider. Its beady eyes showed a trace of consciousness, but that was it. It lay on its belly and sprawled its six limbs outwards. Once the matter was agreed to, Fei Qing stood up and allowed Fei Cai to pocket the two Gu worms.

"Now, it is time to choose your first slave. They are waiting for you outside, son."

Fei Qing spoke up, and Fei Cai followed his father. Opening the door, Fei Cai's gaze landed on four kids that stood straight and proud. Each of them had different characteristics, and Fei Qing casually stated their genders so that Fei Cai could make the decision. He pointed at the two slaves to the left as females and the two to the right as males. Out of the male slaves, one looked quite healthy even if Fei Qing said that he was of the same age as Fei Cai. The youth seemed too burly for Fei Cai to accept.

With a frown, Fei Cai stepped up and scrutinized the female slaves. They were young girls with thin bodies, round faces, and hopeful gazes. Slave trading was a flourishing market within the Northern Plains. The fact still didn't sit satisfactorily with the recently arrived corporate lawyer, and he turned towards his father and spoke up, "Is this really necessary, Father?"

Fei Qing observed Fei Cai and sighed. Just like his son, Fei Qing went through the same spiral of emotions. Fei Qing nodded and spoke somberly, "Be strong, Son. These all were the young masters of the tribes that I conquered. Remember, while they are slaves today, someday, if you show weakness, you could fill their shoes."

Fei Cai turned his head. Though a sociopath that could gradually adapt to Fei Qing's unfatherly teachings, the boy really wondered what would have happened if it was the true Fei Cai instead of him. Giving the thought not a single moment longer, Fei Cai exhaled deeply and observed the two youths as well. While a pedophile might have jumped at the chance of gaining a ten-year-old girl, Fei Cai wasn't one, and he only felt interested by the muscular youth due to his impressive physique and his uses during the hunts.

"Father, I'll take Lo."

Fei Cai wasn't used to naming in the sense of this world and called the youth without many thoughts while pointing at him. Fei Cai's choice managed to surprise Fei Qing once again. The upbringing of the Northern Plains made it so that the younger generation can easily accept the rituals of mating and further the bloodline. Needless to say, Fei Qing was absolutely sure that the other male Gu Masters would have selected female slaves to rut against, and the female Gu Masters are not given the right to choose slaves, so it was a significant detriment for them right from the start.

As if the training was rooted deep within Lo's body, the disheveled youth instantly kowtowed, "Lo greets the Benevolent Master."

Though itched, Fei Cai grew indifferent to the puppy gazes from the other three nameless slaves and then looked at Fei Qing, "Father, I am not accustomed to the traditions. Should I allow him to wear better clothes?"

Fei Cai's inquiry made Fei Qing nod in acknowledgment.

"While I didn't bother taking a slave for myself, you can treat them any way you want. They are trained to remain loyal to their masters, and many Gu worms are used to ensure that fact. This slave can lay his life down for you. Treat this commodity as he should be."

Fei Qing looked at the other two females and felt slightly indignant. Yet, now that his son had already proven that he wasn't interested in the matters of the flesh right from the start, Fei Qing decided to take them away. Either way, it didn't matter to Fei Qing. Instead of a lowly slave popping his son's cherry, it will be his bride. With the matters of the slaves tackled, Fei Cai was left alone as his father departed. He then gazed at the kneeling Lo. "Stand up."

Lo stood up instantly. He was a head taller than Fei Cai, and while this fact could have irked other young Gu Masters, it failed to create ripple within Fei Cai's heart and commanded his slave to follow him inside. 

"Lo, are you acquainted with hunting?"

Lo nodded hastily, "Yes, Master. I can skin wild beasts, and I am taught the basics of Daggers during a battle."

Fei Cai nodded and then looked at his house, "You will clean the house. You will be allowed to eat your food after my father, and I have eaten. Also, you will accompany me in tomorrow's hunt."

Lo nodded, "Understood, Master."

"I will be going to my room. I expect an impeccable result, or you will be punished accordingly." Fei Cai left with these words. He did not have to be polite to a slave with his personality altered to even give his life for Fei Cai's convenience. And as a matter of fact, Fei Cai enjoyed it. The rush and the high brought by the thought of having the ability to control the life of a person with a single command of his. After he entered his room, he sat cross-legged once again and untied the pouch, revealing grey stones of varying sizes. These were Primeval stones condensed with a dense amount of Primeval essence. Primeval essence was the form of energy that was mobilized by the Gu Masters to activate their Gu worms. 

In summary, the jade green sea that filled 69% of his spherical Aperture was actually his Primeval essence. Fei Cai already knew what he had to do, so, he sat and meditated, slowly gaining a basic proficiency in manipulating the Primeval essence within his Aperture before willing a thin strand of Primeval essence to enter the spider-shaped Gu worm and instantly, Fei Cai felt a sturdy wall opposing the invasion of his Primeval essence. Fei Cai opened his eyes only to find the corner-most limb of the Aperture Nurutre Gu to be tainted in green from the edges. 

This was the refining of the Gu worms. Every Gu worms were living beings with their own wills. For Fei Cai to refine a Gu worm as his personal Gu, he would have to overwrite the natural will present in the Gu worm. This was a mammoth task since Fei Cai only felt a slight toll on his mental health. In the next few hours, Fei Cai continued to experiment on the procedure of refinement. His Aperture would recover slightly less than 7% every hour while a single Primeval stone could recover 20% of his essence, although, Fei Cai was sure that this rate would only fall as he cultivates further. Finally, even when Fei Cai couldn't convert the mental toll into units, he quickly found that after exhausting the entirety of his Primeval essence, he could only cover a single limb of the Gu worm and even then, Fei Cai could feel his Primeval essence within the Gu worm fade under the constant assault of the Gu worm's will.

Exhaling deeply, Fei Cai simply remained within his room for the entire night and took continuous breaks after each session to cultivate and refine Aperture Nurutre Gu worm as his vital gu. Success came in the form of mind-numbing exhaustion that made Fei Cai succumb to an unscheduled sleep only to wake up early in the morning with his physically stunned with the morning crust. Rubbing his eyes, Fei Cai sat up and leaned against the wall. 

The actual method of refining a Gu worm for the 'virgins' such as him was to slowly let his will and Primeval essence erode on the Gu worms will and exhaust the Gu worm to refine it in one swoop. Instead, just for the sake of getting a rather great headstart, Fei Cai decided to expend eight of his Primeval stones to refine the Aperture Nurture Gu in a single night. He closed his eyes and focused on the furry spider working on a thin web around the surface of the aperture walls. The spider would occasionally deescalate to dip into the ocean of Primeval essence and would climb up the string to weave its web once again.

Every Gu worm was a living being, and just like human beings, it needed food and nourishment to survive. Usually, the ability to feed the Gu worms would severely limit the Gu Masters, especially young ones like Fei Cai. And aside from its usage, it was Aperture Nurture Gu worm's food that made it so famous. The Gu worm only needed a slight amount of continuous stream of Primeval essence. That was it!

Fei Cai soon rose up from his meditation. The wolf strength gu worm was still within his pocket, and after today's hunt, Fei Cai would refine it, too.