One Piece : Roger Is My Vice Captain - Chapter 12 - Remnants of the old times

Ryu Han-bin, the main character who fell into a new world after being chosen as a ‘suitable person’.

Because of the error in the guidelines, the training is repeated endlessly…

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 ͡°)

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Reborn in a world where martial arts reign supreme, Li Qian becomes a menial disciple of the Divine Sword Sect, assigned as the bell ringer.When ringing the bell, the sacrificial weapon system accidentally awakens, binding his life to the bell as his life-bound sacrificial weapon. As long as he rings the bell, he can enhance the sacrificial weapon.Moreover, the sacrificial weapon has one crucial characteristic.As long as the bell remains unbroken, the host is immortal.From then on, a path of eternal martial arts unfolds before Li Qian....Many years later, when the Divine Sword Sect faces a crisis of extermination, countless disciples kneel before the bell platform.“We beseech the ancestor to take action.”