Sugimoto, Chie

杉本千恵

The mother of the four well-known Sugimoto sisters.
She is older than the other parents in the series, having three adult daughters and one in her final year of high school. Perhaps because of her age, she is wiser and less easily surprised.
She is slightly taken aback when Yasuko announces that Fumi is her girlfriend, though much of this reaction likely stems from the news that her youngest is dating at all, rather than the fact that both partners are female, as she quickly recovers from her surprise. She is very open-minded and accepting, as demonstrated during the conversation she has with Shinako, Kazusa, and Kuri regarding the nature of Yasuko and Fumi's relationship.
She even casually suggests that Yasuko might already have had sex with Fumi, as far as they know (much to the exasperation and embarrassment of the older daughters). It thus seems that Yasuko's lifestyle does not trouble her.
It appears that she was quite popular during her own "glory days," just as her daughters are, and her daughters often tease her for regaling visitors with stories from her past, noting that she will seize any opportunity to talk about her youth.