Her knee-jerk reaction would be to tell him that he should just tell her to leave if he didn't want her around but Billie knows better. If he wanted to ditch her, he would and she would never be able to find him, not if he didn't want to be found. That means his question is a real one and she immediately hates it because she doesn't have an answer for once.

Not a good one, anyway. Not in her opinion.

"I knew exactly how I was going to spend my first life and that's all gone now, all save for you," Billie says. It amounts to a giant 'I don't fucking know' and that's the upsetting part, even if she isn't about to betray just how frightening the thought is. "You've had your entire life to rethink what you'd rather be doing, Daud, but replacing you was what I wanted to do. I'm not going to find something new anytime soon."