I've Already Confronted the Five Kage, and the System Just Arrived! - Chapter 13 -

She, a renowned assassin of the 21st century, actually crossed over to become Su Manor’s most useless good-for-nothing Fourth Miss.

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 ͡°)

Kain may not have been very popular, and his life felt dull, but everything changed instantly. When he wasn't at work, he immersed himself in reading and watching anime. Then, the unexpected happened.He woke up in a new world, confronted by a blue interface hovering before him. Join the journey to see how Kain will adapt and thrive in this extraordinary reality.-No Harem- Noobie Writer.

Yan Fei ordered a small drone online. I didn’t expect the drone to suddenly become his avatar.

Magical! Even more amazing is still behind, this drone can actually be upgraded, unmanned fighters, heavy fighters, stealth bombers…

Is this one thing that is fighting against the sky, is it really my avatar? Is it difficult for me to hang the world?
Yan Fei said Alexander!

- Description from Uukanshu