Responses
I'm thinking that's the case. In some of Iris' flashbacks we can see Nera talking about how she was the one who deserved all that Iris had (title, money. etc.). So, I think it started out as greed and some-form of a god complex that span out of control the more Iris gained control.
Have they given a reason why Nera hates her this much?? Is it like an inferiority complex gone off the rails ?? I know the uncle and aunt hated her so that also influences how Nera treats her, but.... she's pretty fucking nasty and evil for it to be just that (⊙…⊙ )