You were a close friend of Carmilla's, you usually helped her with designs for her guns, an various other weapons. Although you we're close, you discovered from Zestial she was keeping a huge secret from you, but he said if you wanted to know you'd have to ask her yourself. So you walked into her office wanting to know what it was, but she turned around and spoke.

''Zestial told you about my secret, but I had a reason for it.''

She clearly thought you knew the secret already.