Three sisters, Sachi Kouda, Yoshino Kouda and Chika Kouda, live in the house of their grandparents in Kamakura. Their parents are divorced. One day, they receive news of the death of their father whom they have not seen in fifteen years. At the funeral, they meet their half-sister Suzu Asano.
A page for describing UsefulNotes: Japanese Sibling Terminology. Where English makes no distinction between elder and younger siblings, Japanese imōtogo, but these are only used to refer to someone else's sibling in the third person.