|Hair Color||Dark Blue|
|Eye Color||Red and Gold|
|Family||Rikka Kagamiboshi - daughter|
|Voice Actress||Kyoko Donowaki|
Mizue has dark navy blue hair that reaches her waist. Her bangs are in a princess cut and part down the right. Like her daughter, she has heterochromia iridium. Her right eye is a dark red, while her left eye is a dark gold. She wears a light pink lipstick. She is usually seen in a dark purple dress and purple shoes. The collars and sleeves on the dress are white. The dress has a ruby attached to its collar. She also wears gold stud earrings.
Mizue is cheerful and kind. She likes helping people find outfits that "bring out their inner gems". She can also be very serious, especially when it comes to fashion and makeup. Being the head designer of the famous fashion label "RubyS", she is well known for having a keen eye for fashion.
Rikka Kagamiboshi - Her daughter. She gives Rikka advice when she becones stuck on a design. Though they get along, Mizue's optimistic and energetic personality clashes against Rikka's calm and serious one, which leads Rikka to become embarrassed of her mother's lively personality.