Do you think a lazy slug like you deserves the same as people who are working so hard for our nation? You keep saying you want rice, but do you do anything to earn it? No.
- —Seita's aunt to her nephew
After Seita and his sister lose their home and mother to an air raid, they then come to live at their aunt's house, having nowhere else to go. Seita and Setsuko give their aunt what they had left of their mother's belongings so that she could trade them for rice for all of them, despite Setsuko's protests.
While the aunt cares about her nephew and niece, she quickly grows resentful of them due to Seita playing with Setsuko all day instead of going to school or to work since he felt he should stay by his sister's side at all times, relying on their aunt to cook for them and wash their dishes as well as Seita refusing to help the neighbors put out the fire during the bombings and Setsuko crying at night as she mourned the loss of her mother. Their aunt's anger extends to both Seita and Setsuko, who is still too young to study or work, and doesn't waste a chance to chastise them for not doing chores, even telling them to find other relatives to take them in or to move in to the bomb shelter Seita takes Setsuko to during the bombings.
Seita and Setsuko eventually grow tired of their aunt's insults and decide to move into a bomb shelter. Their aunt finds them packing their stuff as she comes home from an errand, she seems slightly concerned about them living on their own but she lets them go anyways and tells them to take care of themselves and gently bids Setsuko goodbye, although she is ignored by her niece. She watches them leave, visibly worried about them despite her earlier coldness.
Setsuko later told Seita that it was their aunt who informed her of the death of their mother, which Seita was trying to keep a secret from Setsuko, this allows Seita to stop trying to hold back his own tears and mourn over their mother's death.
It is unknown what happened to her or her family after the war ended except that she, her husband and daughter survived.
- Kiyoshi Yokokawa (brother, deceased)
- Unnamed husband
- Seita's Cousin (daughter)
- Seita Yokokawa (nephew, deceased)
- Setsuko Yokokawa (niece, deceased)
- Mrs. Yokokawa (sister-in-law, deceased)
- Her first name was never revealed.