Karin Izumi

As the younger sister of Yuzuko and the sister-in-law to Kazuki, this character plays a vital role within the family dynamic. Her connections to both protagonists anchor her importance to the unfolding story, weaving her deeply into the central interpersonal drama. Through these close-knit familial bonds, she serves as a key figure in the lives of the main cast, contributing to the emotional depth and complexity of the series' ongoing narrative.