I Started To Gain Sentience In An Eroge - Chapter 46

Uchiha Yu traveled through and came to the crisis-ridden Naruto world.

Looking at the scarlet writing wheel in the mirror, Uchiha Yu nodded with satisfaction: “Well, everything is going well so far… smooth hammer!”

Looking at the calendar on the wall, Uchiha Yu felt the malice from this world…

In order to save his life on the night of the genocide, and even take food from the tiger’s mouth, Uchiha Yu decided to train Pokémon hard from today!

Uchiha Yume, use illusion!

A trainer: “Referee, Yu’s dream demon is illegal, it uses illusions!”

Uchiha Yu: “Humph, you absolutely cannot escape this technique!”

Deidara: “Explosions are art!”

Uchiha: “My Pangyan monster’s art is better than yours!”

- 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 ͡°)

A biker tries to save a cat on the highway and gets hit by a truck (Truck-Kun), he was rushed to the hospital but, due to internal bleeding, he dies only to be reborn as a cat, in a new world with a system.

In this new and vast world, he tries his best to get used to his new body and get stronger along the way. With his overpowered system and skills. To one day become untouchable.