She lost her parents when she was two and grew up in the Hidamari Garden Children's Nursing Home, along with Ryousuke. She and Akane became friends in high school.
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She is Bossun and Tsubaki's biological mother. When Haru was about to go into labor, Akane drove her to the hospital - only for them to be hit by another car on the way. She died after giving birth to the twins.