Moto Sekai Ichi'i no Sub-chara Ikusei Nikki - Chapter 80 Fallen Castle

Reborn into the world of Yugioh, it's natural if my goal is to become the best duelist!

He is high above, the mysterious and terrible King of the Wild. With one glance, he can see people’s romances. He hates women to the extreme, but at his first glance of her, he dotes on her and spoils her.
She is a humble transmigrator, a miracle doctor who doesn’t care for the many handsome men around her. She only wants to become strong, to be worthy of that god-like man. But when she’s finally sure of her feelings, she finds out she’s already been married for years…
……
When wronged：
She uses strength to hit the big handsome iceberg-like man in front of her eyes. “People say that I’m not good enough for you, but it is you who is an old cow eating tender grass!”
A man seizes the main point and laughs like an evildoer. “This husband has to eat the grass to confirm if it is tender or not!” He puts out the red candle……
……
The world says：
The barbarian king has no heart and has no passion.
A pregnant woman very miserably thinks,” If he has no passion, then who is responsible for this big belly?”

- Description from Novelupdates

In one moment, he was walking down the street with his little sister—In the next, he had traveled to the world of One Piece, carrying a system that could extract, record, and fuse genes to cultivate powerful lifeforms.Thus began a leisurely and carefree life in the most chaotic world imaginable.When bored, he’d snatch a bit of heavenly tribute meant for the Celestial Dragons.When curious, he’d raise a few cute kittens and bunnies just for fun.When restless, he’d wander through the territories of the most fearsome powers in the New World.Life is beautiful—so why bother taking anything seriously?

In every story, there exists the hero and the villain, the protagonist and the antagonist.And like every story, the hero always wins, and always gets the girl.But what happens now that I died and became a villain in the last book I read? Not even a proper villain, but one that the protagonist kills in the early chapters.I don't want to die again, and I don't want that simp of a protagonist to walk all over me. Maybe I should just become a better villain.I've always admired the smart badass villains that took on the protagonist. Maybe I can be one of them, maybe I can win—the first villain to win against the hero.I'll rewrite this story into one where I become the greatest villain. Call me sick or evil, but it's my time to shine.