Sonoda Umi

Umi is a teenage girl with long, straight navy blue hair that falls to her waist and intelligent, honey-colored eyes. She possesses a slender, athletic build and is typically seen in her Otonokizaka High School uniform or elegant idol costumes. Her presence is characterized by a refined, upright posture that reflects her traditional upbringing.

Disciplined, stoic, modest, diligent, shy, and responsible.

High School Student and School Idol

Raised in a traditional household, Umi is highly skilled in kendo, kyudo, and calligraphy, which shaped her disciplined and reserved nature. She is a childhood friend of Honoka Kosaka and Kotori Minami and was initially reluctant to become a school idol due to her extreme modesty. Eventually, she joined µ's as their primary lyricist and strict trainer, becoming a vital pillar of the group's success.