Ten years after divorcing her husband, Ryo struggled single-handedly to raise her son. To escape sleepless nights, she worked tirelessly, and her efforts paid off as her son advanced to graduate school and secured a job. With parenting finally winding down, she was overwhelmed by a sense of loss. Then, suddenly, her son invited her on a hot spring trip, and Ryo set off on a graduation journey alone with him. A new journey begins, one that holds the promise of emotional healing and reconciliation.