Riko processes restored historical records for the Analysis Department, passed to her by Ura. Though initially enthusiastic about uncovering humanity's past through the archives, she gradually lost that passion. She now believes excavating these records only brings sadness, a constant reminder of a world lost through human actions—a past she feels is better forgotten. This disillusionment connects to her grandmother, who once lived on the colony's upper levels before they became uninhabitable and shared stories of Earth's green landscapes, fostering Riko's deep awareness of the loss.

She frequently lies idle on stairs leading upward into darkness, the location where her grandmother suffered a fatal fall. This spot gains significance when Ura later drops a digital device there, displaying a key restored record. Her relationship with Ura is complex; they share a personal archive—a photo of themselves together—implying a past connection. Riko openly expresses her disillusionment to Ura, stating the records "should never have been excavated as it shows only the stupidity of humans" and contain "only sadness which [is] better forgotten."

After a period of absenteeism, Riko discovers the full restored record Ura had not seen at his workstation. It reveals footage showing humanity migrated to the Moon (the "Pale Cocoon") after Earth's environmental collapse. The final segment displays Earth restored to its blue state, contrasting the colony's belief in a permanently ruined planet.