Within a Hollow Heart - Chapter 39: Volume 1, : "The Edge of Darkness"

This story unfolds during the later stages of World War II, where a man, scarred by the horrors of war, finally grasps the profound and harsh realities of the world. In this world, those at the top laugh and celebrate, while those at the bottom sacrifice their lives in futile conflicts driven by pride and meaningless ambition.A modern soul transmigrates and fuses with the original soul of a body, creating a unique and extraordinary existence. To some, he is a villain; to others, a madman.In a world steeped in cruelty, this man, determined to secure a place among the decision-makers, struggles to break free from the ranks of those powerless to control their fate. To achieve his goal, he resolves to shatter the chains of law, then the chains of morality, and finally the chains of mediocrity.

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 ͡°)

One is the gentle and handsome zombie father who has raised her for thousands of years, and the other is the cold and awkward Professor Tianshi who always lectures her. I hate it, why are you digging by Uncle Mei? Jiang Xiaosi bared his teeth, I’ll choose whose blood tastes better… The story of a bouncing little zombie in the Tuoguxiang sex toy store.

- Description from novelbuddy

In this period where countless supporting lead actors always attempt to counterattack, turn over a new leaf or simply refuse to take up the role, his purpose of existing is to fill the role of a good supporting male lead and uphold his duty to the best of his ability. To add the needed lustre to storylines and this world. Only, it’s a pity that someone who is not afraid of god-like enemies will be afraid of pig-like teammates.

Bitterly, he realises that for some unfathomable reason, he is being bothered time and again by a bastard who refuses to follow the script… In order to walk the path of a good supporting male lead, he engages in a battle of wits and courage with that person. Loving each other and killing each other, one ultimately cannot escape fate’s teasing– why is it so difficult wanting to be a responsible and diligent supporting male lead?! QAQ

- Description from novelupdates