Oni Prince

["Indeed, I can fulfill certain requests, even relatively extravagant ones," you replied with subtle inducement.]

["Then... could Lord Goburo take me around the Monster Beast Forest? I've only stayed within Oni territory and haven't seen other areas."

"Accompany you personally? My schedule is quite packed."]

[Kaina's face fell at your response. 'Of course he's busy. Why would someone so important care about my trivial wishes?']

["However, if Kaina truly masters the book, I'll delegate tasks to Gobuma and accompany you."

Kaina froze momentarily before realizing you had agreed.

"Remember, I won't go unless you've thoroughly mastered the material," you reminded.]

[Kaina immediately immersed herself in study.]

[A week later, you escorted Kaina through safer, scenic areas of the Monster Beast Forest. Using the pretext of preventing her from getting lost, you took her hand. Kaina, overwhelmed by the contact, followed obediently. Your presence ensured an uneventful journey.]

[Months later, Kaina became your official concubine. Meanwhile, monumental news spread through the Oni Clan - the Oni Sovereign's child was born with Emperor-class potential, destined to surpass the Sovereign upon maturity.]

[A month afterward, you witnessed the Oni Prince. While ordinary Oni were born at least Elite-tier, the prince had reached Lord-class within a month - a stark reminder of life's inequities. Your two decades of struggle to reach Lord-class contrasted sharply with his innate privilege.]

[Year Twenty: The Oni Sovereign summoned you unexpectedly.]

[Appearing before the Sovereign, you noted his satisfied expression.

"I've heard impressive reports about your domain's development - nearly matching established Lord-class territories in under a decade."

"Your Majesty, I've benefited greatly from fellow lords' guidance and the fertile lands you granted. This achievement isn't mine alone."]

[Your humility pleased the Sovereign. "Since you're so grateful, I have an opportunity for you - a task, if you're willing."

"Your command, Majesty?"

"Become my son's mentor."]

[The request stunned you. Why entrust the precious prince to a non-Oni when numerous Lord-class Oni were available?]

["Don't overthink this. Entrusting my son demonstrates my trust and recognition of your capabilities. I'll be evaluating your progress periodically."

"Yes, Your Majesty."]

[You remained skeptical, sensing underlying issues within the Oni Clan that prompted this unusual arrangement.]

["Come, I'll introduce you to my son."

"By your command."]

[Reuniting with the Oni Prince, you observed the knee-high child surrounded by fawning Lord-class Oni, deep in contemplation.]

[Noticing your arrival, the prince approached: "Father!"

"This is your new mentor. You'll train in his domain."

The prince glanced at you dismissively. Despite your Oni-like appearance and dense miasma, your non-Oni status clearly disappointed him.]

[Recognizing his prejudice against Goblins, you resolved to teach the arrogant youth a lesson.]

["Father, I dislike this teacher. Assign me a Lord-class Oni mentor."

The Sovereign replied calmly: "Though currently Lord-class like yourself, he can defeat Lord-class Oni."]

[The prince regarded you with newfound interest: "Fight me. Win, and I'll accept you as mentor. Lose, and you'll join those losers as my subordinate."]

[Following his gaze, you recognized several Lord-class beings you had previously defeated. Despite the prince's young age - less than half a year old - his ability to defeat these Level 41-50 Lord-class beings suggested remarkable talent, assuming they hadn't held back.]

["Agreed. If I lose, I become your subordinate. If you lose, you acknowledge me as mentor. Correct?"

"Not completely stupid," the prince retorted.]

[A five-meter spectral Oni materialized behind him - the Oni Avatar, a skill typically requiring Lord-class mastery. The prince's ability to manifest it at Lord-class demonstrated extraordinary aptitude.]

[Acknowledging his capability, you remained unfazed, confident in your own arsenal. As the prince charged, you prepared to deliver a humbling lesson.]

[One minute later, the Oni Avatar dissipated. The prince stood before you and the Sovereign, his face swollen, posture remarkably docile.]