Demon Hunter - Book 6 Chapter 32.4

Having transmigrated into the world of Journey to the West and become Tang Monk, equipped with a gaming system that allows for battling demons and leveling up, while looting equipment, from then on, the demons on the path to the Western Heaven were in danger. Monk Sha: Big Brother, it’s not good, another demon has been captured by Master. Tang Monk: You all listen to me today, it’s not you protecting your master on his journey to the Western Heaven to seek scriptures, but rather your master has to drag you all along, you know? Without you, your master alone would have fought, uh, made it to the Western Heaven by now...

“With my knowledge, give me a fulcrum on which to place it and I shall move the world!”

…

Sorcerer Continent—a world where sorcerers exist. Wielders of arcane knowledge. Masters of all elements. Sovereigns of space and time. These sorcerers governed the world with their unrivalled prowess. One day, a young man awakened into this world with his past forgotten and no place to call home. Follow along as Glenn, by relying on his luck and wit, tries to survive and advance in this unforgiving world. Entangled within the machinations of fate, political schemes, power struggles and wars, he forges his own path and creates a place for himself.

- Description from Novelupdates

The Imperial Court of Tang Empire became dim and corrupt. The Emperor believed eunuchs. The officials vied with each other for authority. The Tang Empire was about to collapse. The flouring Confucianism, Buddhism and Taoism eyed it covetously. The three sects wanted to contend for the domination of the whole world. Which one would win in the end? Or would they coexist peacefully at last? Armies of different nations invaded the frontier on all sides. People and the whole world were in extreme misery. Who could save them?

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 ͡°)