I hope the sisters don't have to fight each other. From the ominous title alone I fear the younger sister might become a villain
So, I was thinking about this before too. Does Mia become "evil" in her getting revenge on the country that sold off someone she cares very deeply about?
We know Philia would never endanger someone intentionally which is why she did mostly everything herself. To be fair, Philia was also an extremely powerful Saint so her dong things herself made sense. Mia is not as powerful as Philia so she can't do everything alone.
This chapter makes me afraid that Mia will resort to tactics that would be considered "evil" and while she is doing it for her sister that she loves very much, Philia may still not be able to accept it which could lead to a fight OR Mia turning into a villain for a bit.
I just want to see the prince come to justice for both selling off Philia as well as his plot to kill his own father and then Mia and Philia to be happy sisters over again. Mia has become such a great character because she is fleshed out and her mind is set on helping her sister that she adores and loves and loathes anyone who is mean to her sister.