The Calmly Deranged Eldest Daughter of the Villainous Family

I was reincarnated as the eldest daughter of a duke’s family destined to be villains for generations before facing extinction.
Even the gods are cruel. First, I was a K-drama eldest daughter, and now a romance fantasy novel eldest daughter.
To make matters worse, my younger brother is the craziest person in this world, and my younger sister is a villainess of historic
proportions.

I wanted to escape quickly, thinking I couldn’t spend another life just supporting others, but the villainous descendants turn out to be softer than the rice cakes next door.
“S-Sister, there’s a cat here with an injured leg…”
My younger brother, who’s fretting over an injured cat, grows up to become a villain who imprisons the female lead.
“O-Older sister, the Imperial Princess stole my dress… Waaah!!”
My younger sister, who can’t even retrieve a stolen dress, grows up to become a villainess who pours wine on the female lead’s dress.
“Just trust your older sister. I’ll take care of everything. (You idiots.)”
Damn. Because of my incompetent siblings, I’ve developed eldest daughter syndrome.
I have no choice. I’ll have to take good care of these simpletons to prevent them from turning to the dark side.
* * *

I thought there was no room for romance in my life consumed by childcare, but then…
“My lady, I’ll ensure your delicate hands never have to be stained with blood.”
A sculpture-like, multi-talented butler helps with childcare, and
“Master, did you know cats naturally engage in communal parenting?”
The cat whose leg I fixed steps up to repay the favor.
Wait, kitty, weren’t you the male lead in the original story?
Why are you obsessing over me instead of the original female lead…?