瀬戸 秋

Kimio's first wife and the mother of Shuuji. She died as a result of a degenerative disease.

Very kind and loving, she was a housewife who looked after Shuuji all the time, calling him her treasure. She was excellent in all housework and taught her son how to cook for people who are very valuable to them.

She was also very close to her nieces Tsubame and Aoi. They played a lot together.

Her illness made her lose weight a lot, she gradually lost her muscle mass and also lost her fertility. At the beginning of the "terminal phase", Akio was exhausted and she suffered a lot. However, she had accepted the fact that she was going to die and told honestly to her beloved son that she was going to die, the only thing she was hiding from him was the constant pain she felt.

Despite her indescribable suffering, she spent as much time as possible at home offering the most "happy" memories of her to Shuuji who was alone at home.

One of her last wishes was that Kimio and Shuuji do everything they can to be happy after her death.