How did she even get picked? Is she someone's mistress or something?

Rose isn't a major character or anything so I could understand changing up her race if a Latina or Asian or whatever gave a great audition. But this girl just constantly gives this bored SSRI stare even when she's video chatting her best friend, finding her long-lost brother, or being told she's going to die and have to live in the dreamworld forever and then having her grandmother show up to be sacrificed in her place.