One Piece : Roger Is My Vice Captain - Chapter 366 - 420 - Darkness Devours! Blackbeard’s Crazy Predatory Ability!!

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 ͡°)

Description For a million worth of contract, she became a surrogate mother. He was the chief executive of the Empire and she was of lowly birth. With her adoptive father’s business falling into crisis, she agrees to his contract. She gave birth to twins: the older brother is healthy, while the younger brother didn’t breathe out. Fulfilling the contract with a huge monetary sum as the reward, she disappeared from his eyes. Six years later – he was still the cold high-profile president, but when she is accidentally imprisoned in the cage of his golden birds he pressured her harder and harder: “Woman, do not think you can escape my hands!” The old-fashioned man: “Mu Yazhe, you’d better leave her alone, this is the child’s mother!” The man becomes frightened, questioning the reason this child’s features bears such resemblance to… Associated Names 一胎二宝：亿万首席爱妻入骨

The tale of Oliver.
An orphan boy from a Mine, in 19th century Europe, filled with Magic.

The world’s worst offense, is called Love.