Makio Koudai has always lived life on her own terms. While she maintains a small circle of friends and a steady career as a novelist, she is very introverted and indifferent to social norms. Her relationship with her older sister Minori suffered as a result—her sister's constant criticism during their childhood shaped a lasting estrangement.

At thirty-five, Makio's life is disrupted when Minori and her husband die suddenly in an accident. In the wake of their deaths, Makio meets Asa Takumi for the first time, her fifteen-year-old niece who feels uncertain of her future. With no relatives willing to care for Asa, Makio takes her in despite her hesitance about building a bond with a stranger. Asa struggles to process the loss of her parents and the loneliness that follows, while reminders of her mother quietly shape aunt and niece's routines and interactions.

Through writing and the slow unraveling of their assumptions about family, Makio and Asa learn to understand one another and themselves on their own terms.