"Your world sounds similar," Yin points out, but, well, there are differences, too. Like the moon. That's the big one.

"Our moon vanished," Yin answers. Of course, that's just from sight. It still has to, technically, be there to prevent flooding and issues with the oceans, amongst other phenomena and issues, but Yin doesn't know about any of that. She only knows she can no longer feel moonlight.

"They say the stars changed, as well. Ten years ago." So that's one big way their worlds differ.