The Vampire Cat System - Chapter 219 Konan Amaka 2

A Mysterious continent, with many powerful sect and countless strong one. Juvenile Zhou Heng with a mysterious black broken sword, from the original stone town out into this world of war. Ascended the throne of the world with only a sword in hand.

- Description from Novelupdates

Rhett never expected becoming king until he slayed an ice dragon out of self defense and fulfils an ancient dragon slayers prophecy which makes them to crown him as their king.Transported to a gloomy and medieval like world, he is faced with leading the dragon slayers, the weakest of slayers among other slayers - demon slayers, gargoyle slayers, ghost slayers and shadow slayers.But ruling isn't so glamorous as he had anticipated and he is instead a warrior, with a system like ability which he must level up by slaying Dragons.And to his disadvantage, the world he is his controlled by SLAYERIOUS, an unknown and unseen entity. But that won't stop Rhett, he intends on dominating his world and even daring to slay the strongest dragon still alive, ruieen.And who knows, he might just defeat SLAYERIOUS if he tries harder.[WSA 2025 ENTRY]

People in the World of Naruto: Drinking Makes You Stronger
 Author: Half a Piece of OrangeYouyu, a man who found himself transported into the Naruto world, awakened a rather unusual system:The more he drinks, the stronger he becomes!• Raikage: “What?! I have the strongest defense—wait, why did Youyu just slice through me while drinking?!”• Hiruzen Sarutobi: “That guy’s a monster. I’ve never seen him train, only drink... yet he still cut me down in an instant.”• Madara Uchiha: “Dancing? Tch. That drunk bastard swayed his way over and chopped me up!”• Obito Uchiha: “Damn it! Even space-time jutsu can’t stop that drunk maniac!”Youyu: “My hobbies? Drinking... and cutting people down.”

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 ͡°)