Satomi Kurahashi, a longtime employee at the Flowercrest Department Store Planetarium, has spent a decade working alongside Yumemi Hoshino, an android service robot. After years of Yumemi functioning without incident, Satomi confronts a sudden crisis when the android starts defying commands and vanishing from her station. Tasked with locating Yumemi before her battery fails, Satomi spearheads efforts to diagnose and resolve the malfunctions threatening the robot’s operational stability.

The disruption traces back to a promise Yumemi made ten years prior, now manifesting in her erratic conduct. Satomi’s resolve to restore her colleague underscores both her commitment to the planetarium’s daily operations and her personal investment in Yumemi’s preservation. Colleagues’ anxieties over potentially losing the android amplify Satomi’s urgency, revealing a nuanced interdependence between human staff and machine.

Her role extends beyond technical oversight, positioning her as a mediator between Yumemi’s programmed obligations and the team’s practical demands. The narrative frames their relationship through moments where Satomi’s actions reflect a blend of professional duty and unspoken loyalty, emphasizing the symbiosis required to sustain their shared workspace.