Sonoko is a young woman with dark blue chin-length hair. She has light blue eyes and fair skin.
She is usually seen wearing a black work blazer, a white button-up shirt, and a black knee length pencil skirt.
Sonoko is calm, collected and hardworking. She is very mature but childish at times.
Sonoko is Utaha's editor. They both seem to trust each other and Utaha has never lied to her about her books. However they sometimes can argue about some small things. Sonoko calls Utaha ''Shi-chan" to tease her.