Super Gene Optimization Fluid - Chapter 31: Native Participant!

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

Wen Xuxu is a tenacious, talented, smart and brave woman who was fostered by the Yan family at the age of four when she lost both her parents.

Brought up to be the successor of a huge conglomerate, Yan Rusheng is an aloof, intelligent and arrogant man who is the most sought-after bachelor in the capital city.

Despite growing up together, both of them seem to treat each other as an eyesore. She labels him as a jerk and womanizer while in his eyes, she is a shrew.

Over time, they fall for each other, but they continue to conceal their feelings for each other. By a twist of fate, they are forced into a marriage. And unknown to everyone else and Yan Rusheng, she has harbored a deep secret for many years…

- Description from Novelupdates

In the heavens, where the Divinity resides, there exists the records of life and death.After the fall of the Gryghori onto the earth, the land of man is corrupted. Abominable creatures never before seen are born of the consummation of heavenly and earthly beings and spread across the land to further corrupt the world.A thousand millennia later, humanity has created civilization once again, based on the knowledge left behind by these Fallen Angels.However, in this new civilization,Man is not alone.Nero is thrown into a world infested with demons, the souls of the dead Nephilim, and abominations of all shapes and horrors, when he stumbles across the very eye of the Divine.A story that preludes an apocalypse and the existence of slumbering evil that threatens to envelop the earth begins.This isn't a story of fulfillment or triumph.These are the very Records of the beginning of the end.Welcome— To the Land of the Abominations.

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 ͡°)