My Wives are Beautiful Demons - How does the Demon World work?

The King Of Assassins was a monster that reigned over the world of hitmen for long years. He was the absolute peak that no other being could reach. His name reached the ears of every powerhouse in the world and sent shivers through every human.

Yet, his legend came to an end suddenly when he died in unknown circumstances.

However, instead of disappearing forever, he was given another chance in another world by the goddess of reincarnation. It was the world of an old book that he read back in the time. A world where everything was possible, where humans could reach new heights that were impossible in his old life.

But, this place didn't seem to be normal as it carried a huge surprise that will make his journey seem all the more interesting.

The Goddess of reincarnation wasn't as holy as anyone would think. She was nothing but a twisted being who found a toy to play with. The goddess manipulated the world that he was going to and changed all the heroines into these twisted beings that fit her character. They were all now harboring this unhealthy obsession toward him and trying with all their powers to take him away for themselves.

Karl, a young man stuck in a rough patch after losing his job and burning through almost all his savings, wandered through the cold, dark streets of Eldoria. On the damp, silent sidewalks, he stumbled upon something bizarre: an old gacha machine mysteriously appearing at every corner he turned, almost as if it was following him. Driven by a mix of curiosity and the overwhelming weirdness of the situation, Karl finally gave in and used his last bit of money on the machine. From the gacha ball, he pulled out a card with a barcode.Back in his cramped apartment, curiosity finally won over caution, and Karl scanned the barcode. To his shock, an app called “Common Sense Manipulation App” installed itself on his phone, claiming it could alter people's “common sense.”------Support Me By Gifts or Power Stones-----

After being imprisoned in the basement by her mother for ten years, she ended her cruel and tragic life in death when they forced her to hand over the key to the hidden treasure. Getting reborn in her teenage years, she woke up in the bed of that terrible and powerful man. This time, she must take revenge on her enemy, and now she must live.

A third-rate painter in the past life, and a chaebol in this life.

I thought it was a rebirth flow, but it turned out to be a system flow. I wanted to rely on myself, but you let me use a plug-in.

“Ding! Congratulations on successfully signing in to Mao Lilan. You will be rewarded with a Dacheng-level “Karate”, which the host can receive at any time.”

“Ding! Congratulations on successfully signing in Gin Wine, and a reward of [Servant Contract], which the host can receive at any time.”

“Ding! Congratulations to Suzuki Ayako for successfully signing in, and you will be rewarded with a copy of “Cash Capability”, which the host can receive at any time.”

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- Description from novelbuddy