Didi's feed

I am kinda scared that Raphtalia is now a part of the other world like she is the new holder of the katana, right? And it is a part of that world so either Raphtalia has to stay there (bc she isn‘t a slave of Naofumi anymore like she is now the new holder of this vessel so she needs to stay?) or she can leave that world and return with or without the katana. But then the other world would lose one of the vessels....╥﹏╥