Thirteen-year-old Hina Satō lives with her father in temporary housing within a Miyagi Prefecture port town, her life permanently altered by the 2011 Tōhoku earthquake and tsunami that claimed her mother's life. Despite this profound loss, she maintains a cheerful disposition. A deep passion for figure skating drives her forward.

Hina once buried a time capsule at age six. Its rediscovery during her adolescence becomes a pivotal event, spurring her to confront buried memories of her mother and the disaster's aftermath. Her character development focuses on reconciling these painful memories with her present life and future aspirations. This journey of reflection helps her navigate grief while strengthening her resolve to pursue her dreams, highlighting her resilience in moving forward.