Satsuki Aoyagi is a quiet and shy nurse employed at Ishikawa General Hospital, deeply committed to excelling in her demanding profession. Despite her dedication, she struggles with clumsiness and frequently makes errors during her duties. Her initial mistake involves administering incorrect medication to a distressed male patient. This patient manipulates her into addressing his resulting physical condition through sexual activity, an encounter that unexpectedly awakens pleasure in her.

Following this incident, Satsuki adopts a pattern of using sexual encounters to conceal subsequent mistakes at the hospital. This behavior escalates through repeated use, creating a precarious cycle marked by the constant risk of discovery by colleagues. The hospital environment itself is challenging.

Her story involves complex interpersonal dynamics with other staff members, including Dr. Waka, Naho Ota, and Nakamura Midori. These relationships introduce complications such as elements of a love triangle and instances of collaborative sexual encounters between colleagues. Her background outside her nursing role is not detailed. The character's development occurs solely within the events depicted in the OVA narrative.