MTL - The Great Voyage: the Prop Master on the Straw Hat Ship - Chapter 534

Here martial arts are no longer intangible legends. They have been passed on from generation to generation and from century to century. After the confrontation with science and technology, they have completely integrated into modern society and all kinds of martial arts competitions are taking place across the country as superiority among scholars are hard to reach a consensus but not as difficult among martial artists!

Doomsday comes, and human beings enter the heavenly world.
Ten years later, Yang Chen, who was betrayed tragically, returned strongly with the Tianyu bug. In this life, he vowed to make the betrayal pay the price. He has a powerful bug bonus, just like an open hang. Frightened to hear…

- Description from novelbuddy

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 ͡°)

[Longevity + Discipleship + No Female Lead + Lighthearted Humor with No Tragic Moments]When his master picks food, he spins the table there;When his master chants spells, he chats without a care;When his master takes rest, he sings a lively song;When his master lies late, he bangs the pot along;His master lives on long, but his life is rather short;His master lays him down on the hillside, as a sort;His master lifts a cup, but he won’t take a drink;His master shares a tale, but he won’t stop to think;His master holds a feast, but he leaves the table wide;His master calls his soul, but he’s nowhere to abide.Spring returns to the hills, with blooms so bright and fair,Yet master and disciple are parted, one in heaven, one elsewhere.