Empress of Otherverse - Chapter 85

After crossing over to Naruto World, Shiranui Yuuji found that there was an incomparably terrifying Godzilla in his body.

“You are Tailless Bijuu? Your chakra is astonishing…. What a coincidence, so am I.”

“You know Bijuu’s coat? I don’t have Bijuu’s coat, but I do have Godzilla Coat-”

“Bijuudama is terrifying!! It can destroy a mountain as soon as he sends it down?”

Hiss, that Bijuudama scared Yuuji, he quickly moved his hands to form seals,

“Nuclear Release – Atomic Breath!”

When Yuuji turned into Red lotus form, Godzilla pressed Nine-Tailed to the ground.

“Nine-Tailed, your strength is too strong. You need to be fried…”

Nine-Tailed, “?”

“What Jinchuriki are you exactly?”

Back in 1991, in the face of this golden age, Chen Jianghai swears that he will only live in three words in this life: Lin Wanqiu! The story of a reborn person who built an electrical empire and reached the pinnacle of his life!

- 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 ͡°)

After being awakened from their slumber, billions of people found themselves dispersed in various sealed crypts. Surrounded by earth, they each had only a shovel.