Exploring Technology in a Wizard World - Chapter 640 - 638 Lancaster Castle

This is a world where humans, demons and mysterious beasts coexist.

Humans cultivate mysterious qi. Demons cultivate corporeal bodies. Mysterious beasts cultivate soul perception.

A legend says that in the middle of an endless rainforest, there are extremely powerful existences; they are called demon kings.

Some demon kings have a tyrannical corporeal body, some are experts in illusions.
Some demon kings are proficient in magic, some can even move mountains.
Some demon kings are able to sense things thousands of miles away.

These demon kings rarely appear in the human world. Even if they emerge in the human world, they would reincarnate in human form; assimilating with mankind while seeking to breakthrough realms…

- Description from Novelupdates

There’s an ancient saying in Great Ruins, ‘Don’t go outside when it’s dark.’

Leon Walker, the world-weary genius of modern world, is killed in a freak accident — the notorious Truck-Kun makes an appearance. Death is only the start. He finds himself reborn in a new world, Galvia, reincarnated into the strong but failing body of Duke Leon Moonwalker, one of the only three Grand Dukes of the Moonstone Kingdom, a minor but strategically powerful kingdom within Galvia. As Leon attempts to understand his new world, a strange voice resonates in his head. “Supreme Spouse System Activated.”.