Ep. 3: Airi’s daily routine changes when she befriends Yumie and stops watching the mysterious woman.

Middle school student Airi spends her days walking to school alone, watching a woman in a high-rise window each morning and listening to a radio host read letters each evening. She suspects the letters are from the woman, and their silent exchange becomes a cherished routine. This pattern shifts when Airi shares her math book with classmate Yumie, leading to a close friendship and shared commute. Consequently, Airi abandons her window-watching and radio listening habits. Unaware of this change, the woman in the apartment decides to meet the smiling girl. One morning, after Yumie stays home sick, Airi walks alone past the building. As the woman leans out of the window, a billboard featuring her image suddenly falls into the street, narrowly missing Airi.

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