That's a more clearly defined purpose than she's used to humans having and it's quite strange. But what he says also seems familiar, in a way. "It can be difficult to realize one's own captivity until one experiences true freedom," she agrees pensively, thinking back to a very, very long time ago, before the Doctor. "One might never know anything else." And what a pitiful fate that would be.

It's also rare to meet someone whose life has actually been improved by being taken by the rift, aside from the child the Doctor brought home. "I assume you will not want to return to your own universe, once you can?"