[She had noticed, a bit, but the lines of his arguments sometimes jumped around, found new anchors or theoretical scenarios to measure against.]

That's... [A really complicated thing to answer. She frowns for a moment, tries to think of where to start.] Headmistress Sparrows, she gets all these girls - like me, you know. [With pathoses, she means.] Has us do lessons, and training. Sends us out on missions.

You live long enough, you're perfect enough, maybe you get made an instructor. Then you're teaching and training the next load of girls.