I am wondering if Nemesis can just leave and let behind its host, more or less unharmed. Because I've been thinking what could happen with Justine as the baby grows and there is a chance that Nem-Justine realizes the Hunger is weakening her and the risk for her host is big, so Nemesis just jumps from her to another host (probably random). If that is the case, Justine will find Harry and ask his help (he probably will soulgaze her, because he is soulgazing/sighting everyone now). Another option is that Nem-Justine tries to blackmail Harry the same way that it blackmailed Thomas, to ask him for something that would help it, perhaps to ensure the delivery but with a way of escape. Of course, it that is the case, it won't work as planned but it will escape, perhaps back to the NN.