1. An interesting person who is exciting, beautiful, and a good friend. Just don't take it beyond friendships -- She's the best friend you'll ever have, but once you even think about taking the next step she'll find a way to rip your heart out.
2. A liar: Sierra usually says she's not ready for relationships because she is "not over" her last heartbreaks, but not a month after telling you that she'll have her newest boy-toy victim.
4. A person with a lot of potential, and likes to help people. Most often herself.
Sierra Roberts is crazy cool, it's too bad that I can't be friends with her anymore after she ripped my heart out and stepped on it.