Comment by Beast Gohan on I Became The Duke’s Male Servant - Chapter 72

First, she betrayed Rosalia when the older prince gets engaged to Nora because she's from "the bloodline" to use her and become the crown prince, but she naively thought he loves her, and when Roselia reveals who she is, automatically the Empress' son is the one chosen as crown prince because he's got Roselia on his side since she's of a much higher and noble status than Nora.  Then, obviously, Nora is looked down on since she's an orphan from the slums and very jealous of Roselia so she attacks among other things she's caused to Roselia because of her jealousy, and when I said Nora betrayed Roselia, because Roselia saved and helped Nora, yet she still got greedy.