Spoiler for Episode 1:
Oh, Seio Academy. How nostalgic. It's a bit harder to believe that Chihaya is male like Mizuho before him because of his soft feminine voice. Then again, it seems he is better at disguising his voice than Mizuho. Kaoruko is called the Knight Princess, huh. She's good at fencing, too. And Eri Kitamura is her seiyuu. Knight Princess. An appropriate title in more ways than one. I like her already.
I see Hisako Kajiura-sensei is a returning character. Though she looks different now. Her seiyuu Yui Sakakibara also reprises her role as Kajiura-sensei.
Man, why couldn't this have become a full TV series instead of a 3-episode OVA.