An elegiac story of two young cousins coming of age at the Japanese seaside.

Maria has grown up at the seaside alongside her cousin Tsugumi, a lifelong invalid, charismatic, spoiled and occasionally cruel. Now Maria is moving to Tokyo to go to university.

When Tsugumi invites Maria to spend a last summer by the sea, a restful idyll becomes a time of dramatic growth as Tsugumi finds love, and Maria learns the true meaning of home and family.