Since she grew up in a family where she was transferred a lot, once in kindergarten, 4 times in elementary school, 4 times in junior high school, and once in high school. At that time, she and Hana were classmates for a short time before the graduation ceremony. Since she had only talked to Hana once, she couldn't remember Hana that much only that one time when Hana helped her find her lost key.

Spoiler

Just before the school festival, she transferred to the same high school as Hana as a second-year student, and found Hana and go to talk to her. However, because she thought that Hana was a second-year student like herself, Eiko and others became aware of the fact that Hana was a ronin.