I don't understand why is celphi mad? Perhaps I'm just half asleep but can someone explain...

Celphi thinks the Duke doesn’t deserve Pereshati because the Duke used his blood (potentially killing her) to test her revival when they first met.

I can’t recall the exact chapter, but that’s from what I remember. There was 1-2 chapters where Celphi found out that happened and basically lashed out at the Duke for doing that.

Oooh thanks, I remember now