Current Princess of Serpents, daughter of Silvia Silverstone, and twin sister of Sam Silverstone. She is sassy and is childhood friends with Jasper and Viktoria Jones. She is in love with Jasper. She has never been to Midgard though her father does tell stories of his time there.

"She was rather short with bobbed green hair and black eyes. She was dressed in a long black dress textured to look like scales. Shawn guess she was around 14 or 15."- Description of Sierra in Book Three Shawn's Chapter.