Moto Sekai Ichi'i no Sub-chara Ikusei Nikki - Chapter 23: Limptfert Dungeon

Shu Yu transmigrated and became the original novel’s violent and brutal female Demon that caused the supporting male character, AKA hidden Boss, to become batsh*t crazy. However, right now, the Boss is just a lowly slave that was just given to her. What should she do?

- Description from Novelupdates

A villainess known by all as a wicked woman who has done all sorts of evil deeds—Ducal Lady Violet.
She regained her memories of her previous life after she fell into a lake and almost died.
The very moment she woke up, she immediately visited her father, Duke Everett, and asked one thing.

“Please confine me to the annex.”

And so, she imprisoned herself there.
Now that Violet was secluded away from the world’s criticism and reproach,
She immersed herself in her previous life’s memories and started painting them.

“What the hell are you up to this time?”

Everyone was suspicious of just what she might be scheming.
However, the misunderstandings surrounding her gradually got resolved one at a time…

‘I want to travel to a place unknown to the many…’

It was a passing wish to the weary and tired Eugene and she’d not think it’d ever come to pass… but it did.

She opened her eyes and found she was sent to a novel-like world she wrote in passing and became Jin Anika, the scorned queen notorious for her ruthlessness and undeserving of her status.

Queen Jin only sought and desired to see the destruction of this world — the villainess who met her untimely and miserable end at the hands of her husband, Kasser, the reigning king of the Fourth Kingdom.

While struggling to survive in the unknown world, King Kasser visited Eugene and demanded that a contract be fulfilled and come to fruition.

“Three years ago, we made a deal.”

It turns out the Queen was under a contractual marriage with King Kasser. The ultimate price? To bear him a child.

“A… a child?”

“Yes, my successor.”