MTL - Dragons Flies Phoenix Dances - Chapter 48 Sex and hateful knots are difficult to solve (3)

An alien race invaded the Earth on June 6, 2128. At the midst of this war, many nations allied with the alien threat and the war nearly wiped out the rebelling humans of the planet. At the edge of mankind's survival, the United Nations Army launched its forces to eliminate the immediate stellar threats that loomed over Earth.

General Seeker Carlean, commander and leader of the mission, risked and gave his life to destroy the immediate stellar threat. The battle was won though Earth lay in ruins. Perhaps mankind will live to see a few years of peace before the alien threat returns to wipe out their existence.

At the immediate aftermath of the stellar battle, the fallen Seeker Carlean awakens and finds himself at aged 17, living the peaceful life he lived 16 years before he died.

So begins a new game in the battle for humanity's survival.

Existence was divided into three realms. The Heavenly Realm. The Earthen Realm. The Infernal Realm. Below them, countless minor realms of all types existed, none able to match the might of any of the Three Fundamental realms. The Celestials led the Heavenly Realm, The Immortals led the Earthen Realm and Demons led the Infernal Realm while the Rulers controlled all the minor realms. Together, they formed The Myriad Unity and allowed peace to reign supreme. The mortals were allowed to cultivate and reach for the Heavens as a balance was installed between the Heaven and Earth, all according to the Heaven’s Will. And yet, among the billions of trillions of living beings within the Myriad Unity, one seemed unsatisfied. “They are lying to us.” This man went against all known truths and contradicted the very gods. “We are in a false world! Mere pawns used to study an outcome!” And so in search of freedom and truth, this man committed the ultimate taboo. He rebelled.

When she woke up, Lake returned to the classroom of the third year. The classmates were in class with swords and sticks, and the teacher became a female Taoist.
The little fat man in the back seat, how to put two big hammers under his chair.
Rick found this to be a global era!

- Description from Uukanshu (translated)

This is a world where a king is the most powerful.