The Lustful Young Master is Sinister! - Chapter 231: Exploration -8:

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

Zhong Yuhuan had transmigrated into a book and became the female supporting character who was destined to die an untimely and tragic death. Coincidentally, her family adopted two boys — the male lead and the villain of the book! The male lead of the book would become a superstar in the show business and the villain a super successful and powerful businessman. Zhong Yuhuan thus began her life of raising the male lead and the villain while faceslapping other scums. She would grow up quickly and live the life of the rich and powerful Mary Sue!

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 ͡°)

Reborn into a failing noble family, Liu Xingchang awakens in a weakened teenage body, surrounded by humiliation and betrayal. Once the revered Sword God of the Northern Polar Heaven Domain, he now faces ridicule from his former lover, Yu Qiuer, who has abandoned him for a rival, and scorn from the very man daring to tread on his legacy.Though his power has diminished to a mere third-grade cultivation, Liu’s indomitable spirit drives him to reclaim his path to supremacy. When he fatally strikes his foe amidst the disbelieving crowd, even the noble Princess Qingyuan is drawn to this fallen “”coward’s”” defiant strength.Can Liu Xingchang resurrect his family’s honor, ascend to the Divine Realm, and turn the tables on those who scorned him?