I Can Create Perfect Accidents - Chapter 129 - : Butterfly Effect?

With the ability of the King of Silver, the first king in “K”, to be immortal and immortal, he crossed into the world of One Piece. Although he became a Pirate, he did not target One Piece.

His goal is to live freely on the sea, it’s that simple.

- 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 ͡°)

One day, Song Shuhang was suddenly added to a chat group with many seniors that suffered from chuuni disease. The people inside the group would call each other ‘Fellow Daoist’ and had all different kinds of titles: Palace Master, Cave Lord, True Monarch, Immortal Master, etc. And even the pet of the founder of the group that had run away from home was called ‘monster dog’. They would talk all day about pill refining, exploring ancient ruins, or share their experience on techniques.

However, after lurking inside the group for a while, he discovered that not all was what it seemed…

- Description from Novelupdates

Introduction to One Piece’s Bounty System: Tianlei crossed the One Piece World and become the nephew of the Navy Admiral ‘Sakazuki, ‘Akainu’, Tian Lei thought it was very outrageous until he found himself having a [bounty system] that can be exchanged for everything in the world of One Piece. As long as you kill or capture pirates, you can draw a Skills, weapons, and devil fruits. Such as ‘Navy Six-style’ ‘Overlord color Haki (Busoshoku Haki)’ ‘sense color Haki (Kenbunshoku Haki) ”armed color Haki’ ‘devil fruit’ ‘sword skills’ have everything!

- Description from Novelupdates