Koko is a student in Class 3-3 of the Kazemi-affiliated junior high school, and a childhood friend of Yoshiyuki and Nanaka. In the first season of the anime, she confesses her feelings to Yoshiyuki; he accepts them, and they begin dating. However, later in the first season, she breaks up with Yoshiyuki after it comes to light that he has been spending too much time with others, particularly Minatsu. As a result, Koko feels left out and develops insecurities due to Yoshiyuki's insensitivity to her feelings of loneliness. Koko is shown to have been weak and to cry frequently when she was young. Only after much persuasion from Yoshiyuki does she smile. Koko also displays a forgiving personality, as seen when she quarrels with Yoshiyuki in their youth but forgives him after he apologizes. In the second season, she develops into a more confident individual, though she still shows signs of weakness by falling ill for unknown reasons just before the puppet show, in which she is stated to play the female character.
No comments