Naomi may have thought back then that Rae was human. As she can be pretty pig-headed, she may even think so still. But I'm in no doubt that when Rae says that she is a succubus she is telling the truth.Exactly what I said? There is a scene early on, where Rae says something like "you humans ---" and Naomi calls her out on it and Rae acts confused and Naomi accuses her of being coy then eventually lets it go. She 100% implied Rae is actually human.