Nice To Meet You, Mr. Xiao - Chapter 31 - 43 Xiao Mohan, You Actually

An anime otaku who has traveled to the world of full-time hunters, in order to live well, he can only keep getting stronger all the time, burying the strong one after another. Your withered life will be continued by me.

- Description from novelbuddy

Lucifer travels to the world of One Piece, binds the system, and obtains the fruit of words and the power of hell demons at the beginning.Everything Lucifer says will become reality, and matter can be summoned or generated through sound.Flash, lightning, fire, ice, magma, gravity, earthquake, all powerful abilities, Lucifer can use.By beheading enemies, Lucifer earns kill points, which buy more powerful powers.Akainu: As soon as Lucifer speaks, my magma can only be used to light candles.Kizaru: As soon as Lucifer opened his mouth, my flash was slower than a turtle.Whitebeard: My Shock Fruit can't shake a rock.Kaido: My immortality has failed.Redhead: Why is my strongest Conqueror's Haki gone?Five Elders: Please, stop talking.Lucifer: I haven't done it yet, why are you so stupid?Everyone: You didn't do anything, but you did.Lucifer: A gentleman uses his mouth but not his hands.From then on, a hell demon who used his mouth to attack invincible opponents all over the world was born.Disclaimer: This is Translation

When an era came to an end, various forces set foot in cultivation to compete for immortality. A young boy who spent most of the time sleeping got lucky in the troubled times and became an unparalleled immortal who could cover the sky with a snap of fingers. Was he going to live forever?

- 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 ͡°)