Kotsuru Kabe is among twelve first-graders taught by Hisako Ōishi at a rural satellite school on Shōdoshima island in 1928. Her childhood forms part of the original class embodying the "twenty-four eyes" of the narrative's title.

Her background is rooted in the economic hardships of prewar rural Japan. Like classmates, limited opportunities arise from family circumstances. By 1941, approximately thirteen years after starting school, Kotsuru achieves honors in midwifery, pursuing education and professional training despite societal challenges.

During World War II, Kotsuru moves to Kobe, working in a café, indicating financial necessity or wartime displacement. This shift from healthcare to service work reflects broader wartime disruptions.

Surviving the conflict, Kotsuru attends a class reunion of surviving students in 1946. There, she joins her peers in presenting teacher Ōishi with a replacement bicycle reminiscent of the one ridden during her early teaching years.

Her presence at this postwar reunion signifies endurance through the turbulent decades of militarism, war, and reconstruction. Kotsuru's trajectory—from childhood poverty to professional training, wartime displacement into urban service work, and eventual participation in this symbolic gift for her teacher—traces the impact of historical forces across twenty years of Japanese history.