Days with the demon queen - Chapter 15: Mastermind

Orlax Tirshtain is the villain in the global game [Unification of Empires]. The tyrannical, cold-blooded emperor is a man who slaughtered his own family with his own hands and ascended the throne with their blood—a power-obsessed madman. Despite five years having passed since the game’s release, no one has been able to defeat this lunatic. So, how the hell did I become this damned?????

【The most sensational fantasy novel on the web, with over a billion clicks – highly recommended!】To seize the 'Source of All Things', a treasure that could propel one into the realm of gods, the great Nine Nether Heavenly Emperor fell. Reborn as a youngster named Shifeng,watch how Shifeng, with the revived memories of his former life, eliminates geniuses from all around, captures the essence of heaven and earth, and climbs atop piles of bones back to his throne of an emperor!

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

Cho Ryu Hyang was good at math from a young age. When he enrolled into the The Theoretical Maths and Martial Arts School, the teacher, Jo Gi Chun, recognized Cho Ryu Hyang’s talent immediately and took him in.