With the Kuremisago emphasis on eugenics, how Miu and Shigure having some similar features (that's not just the boobs), and how Shigure is an orphan and basically got hidden when she was young. I won't be surprised if it will be revealed that Shigure is descended from Kuremisago and she's likely...
If there are millions of early Americans that got whittled down to a few thousands then it's still viable to make a nation. Especially if there are immigration.