Reincarnating Into The Daughter Of A Villainous Duke's House

{If you like the Novel 'The Way To Protect The Female Lead's Older Brother'} it will be similar with a little twist.

After a sudden death, I possessed the body of someone in a 19+harem novel.
I became Viliana Valdimir the daughter of Duke Frediko Valdimir a pshyco villain who raised his many children as cattle to take over their enemy, the Heros royal family.

Duke Frediko had secretly kindnap Prince Oron Von Heros, ensalved him, and chewed him like a toy in the novel. But when Prince Oron miraculously escapes he will come back and wipe the Valdimir Duchy out of existence.

But what if I avoid his kidnaping and I strike a deal.

"Why would the daughter of the Duke Frediko help me?" -Oron (Age,19)

"There is no reason why your savior should have to explain to you"- Viliana (Age,17)

"You must want something in exchange then ?"- Oron (Age,19)

"You are correct, so make sure to remember today I have saved your life."- Viliana (Age,17)

"A life for a life your highness, that is the exchange I ask for saving your life"- Viliana (Age,17)

We have made a pact, even so the Valdimir Dukedom family is meant to fall by his hands...

But this time I will take that role away....it will belong to me.

P.S
THE COVER DOES NOT BELONG TO ME, I FOUND IT ON GOOGLE AND EDIT IT.