MTL - The Ninth Sister is a Prodigious Beast Master - Chapter 82 mutant king

The Red Dragon came from the vast wild wastes, coveting all the strength in the world. It once had countless titles: Mountain's Wrathful Flame, Infernal Calamity, Crimson Emperor, Ashen Dragon......The world trembled under the shadow of the giant dragons. He stirred up the craze of the magic industrial revolution; in the empire he established, Wyverns roared, artillery fired in unison, and steel beasts appeared in the sky and on the land, while disasters from another world rampaged everywhere.“Submit, or die.”Cassius spread his wings, blotting out the sun, and gazed down at the trembling humans, elves, and dwarves below, saying thus.......It is a story about a Red Dragon with a player template conquering, ruling, and transforming an alternate world.(Pseudo of DnD, The Fourth Calamity, Red Dragon)

Rudel Arses, the first born of one of the ‘Three Lords’ of the Courtois Kingdom, is from a corrupted family, but at 5 years old, he saw a dragon in the sky and his dark future as a villain changed. He was considered an idiot, but was that true? How would his effort to become a dragoon change the kingdom?

As the last abyssal demon in the world, Wen Long was pulled into various worlds to do tasks by a guy who claimed to be a system. The goal of her mission was to save those villains who had been blackened for various reasons…

- Description from Novelupdates

Dual cultivation isn't a choice; it's a necessity.

After being struck by a truck like most lucky protagonists (or unlucky ones), Vaan found himself transmigrated into the body of an orphan in the world of witches and demons.

However, they didn't always exist.

Demons terrorized the world ever since the Gehenna Realm descended over 300 years ago. but along with them, came mana, giving birth to witches to combat these demons.

Since then, the world of men was dominated by witches, establishing the seven witch kingdoms, which safeguards at the forefront of the demon invasion.

In order to survive in the matriarchal society of the witch kingdoms, Vaan, like all other men who cannot use magic, had to learn how to service the witches to survive.

Nevertheless, it did not come without its own benefits.

Years of research have led the world to the discovery of intimacy between men and women could increase the witches' mana absorption.

But at the same time, men could absorb some of this mana to improve their physique and lifespan.

Thus, since then, an intricate relationship was formed between men and witches in the red-light districts. Love became casual, and dual cultivation is common.

As a prodigy in the art of pleasing women, Vaan lived a smooth two years since his transmigration as an orphan.

However, everything came crashing down in a heartbeat one day when his life was nearly taken, and Lady Eniwse whom he served went berserk.

Even so, that was not the end.

With the awakening of the Witch Hunter System, watch how Vaan takes on the world and becomes the lord of witches.

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Note: Contains lemons.
Hunting witches does not necessarily imply killing witches if you know what I mean ( ͡° ͜ʖ ͡°)