Am I Actually the Strongest? Manga, Vol. 2

I got thrown out of the family the moment I was reincarnated as a baby! But I'll survive with my overpowered magic! After saving his mother and sister from empire soldiers, Haruto's younger sister, Charlotte, grew attached to him. But that's not all... She mistook Haruto for a hero of justice!! Now, he plays along and calls himself the Black Knight as he ventures out to protect the frontier region. But to his surprise, he finds out the truth behind the mastermind who's targeting his family...!