Ruby is a rich girl who was born into money. She's never had to work a day in her life, and it shows. She's an example of someone with everything but provides nothing. She's condescending, rude, entitled, and doesn't care about anything or anyone. She's here to have a good time, and if anyone or anything gets in her way of doing that, she'll have a problem. In Ruby's world, it's Ruby first and everyone else second.

High-to-moderate pitched voice. Ruby is your classic spoiled rich kid, so the voice that comes to mind based on that depiction is probably an accurate one. If you can make Ruby sound obnoxious, then you'd be a good fit for the role.