This question actually catches him a trifle unprepared. What would he call her? 'Pet' simply didn't fit. 'Test subject' didn't, either, since he wasn't really going to be running any tests. He meant to observe her and learn from those observations, nothing more. He shakes his head. "I haven't yet found a word that fits. It's true I wish to study how you hunt and kill, how you consume your prey; I wish to learn why it is vampires prey on humans, specifically; and perhaps I'll learn enough that I can close this chapter of my life and move on."

He eyes the collar for a moment. "And once that's done, perhaps I'll simply set you free. I don't know, yet."