Sara Shida, Arata Iura
High school student, Yo (Sara Shida), lived with her father, Nao (Arata Iura), after her mother, Sachiyo (Hikari Ishida), left the family when she was very young.
However, their life together came to an end and they started a new life as a family of four with her father's second marriage partner, Miko (Akiko Kikuchi), and her stepdaughter, four-year-old Hinata.
She confides in Riku (Oji Suzuka), who belongs to the same art club as Yo, about her confusion about this new life. Yo, who has been developing curiosity for her biological mother, Sachiyo, promises to go with Riku to Sachiyo's art exhibition.