My Stepdad Was the Mastermind

I only tried to protect my mom and our family, but somehow the mastermind villain got involved?!
* * *
My uncle disappeared six months ago, and my grandfather suddenly died in an accident.
Because my mom is legally unmarried, she cannot inherit the title or the family property.
To make things worse, my mom’s cousin—someone we firmly believed was on our side—made a ridiculous proposal.
“If I inherit the title, how about you marry me?”
Marry him? How could that ever happen?!
He wants to take everything we have, and even take my mom for himself!
It was unbelievable, but at this rate we would lose everything and end up on the streets.
We only had three months to fix everything.
If my mom wanted to inherit before that, the only option was for her to get married.
I, Valerie Arno, am a reincarnated person, so I checked the story of the novel and found someone who could be trusted completely.
Everything was going smoothly, and my mom was about to marry him when…
“Please report that Klaus Dekaran of the Duke Dekaran family has come to meet His Majesty the Emperor.”
…Who?
Klaus Dekaran?
Not Marcus Olden?
The man I carefully chose to become my mom’s husband is the mastermind villain from the original story!
What in the world is going on?!