She is Sunako´s adoptive mother, since Sunako is the head of the family.
During their short date, Chizuru reveals to Ozaki that prior to becoming a Shiki, she was married but had no children. Her husband died in a war in the South. And that a knife slipped onto her hand from a taro potato.
She targets Ozaki Toshio and sucks his blood with Seishirou's aid. However, her hypnotism doesn't work on him, as Toshio has already been bitten by Natsuno who ordered him to always make things by his own will, so Chizu ru's orders only take second priority. Toshio then lures Chizuru out on a date with him to the village's festival. There, he e xposes her nature as a Shiki, and together with Mr. Shimizu (her victim's, Megumi's father), impales and kills Chizuru. Her death starts the all-out war between the villagers and the Shikis.