Sayaka Kisaragi holds the position of sub-commander and instructor at the Shimoji Airbase. She retired early from active duty as a Meteor Sweeper pilot for undisclosed reasons. Reporting directly to Commander Robert Reynolds, her primary responsibility involves training candidate pilots Mikaze Honjou, Shizuha Doi, Ayamo Nakamura, and Karin Kikuhara. Disciplinary actions, particularly toward Mikaze, frequently mark her student interactions.

Her personality presents a distinct contrast. As an instructor, she maintains a strict, uncompromising professional front, earning a severe reputation. Outside this role, especially around fellow instructor and pilot Kazuma Iwasaki, she reveals a more refined, friendly nature. Her behavior toward Kazuma includes active flirtation, escalating to uninhibited advances when intoxicated. This contributes to a love triangle involving Kazuma and Kouchin Restaurant waitress Ran Mikuriya. Sayaka responds to romantic rivalry with visible jealousy and sharp criticism directed at other women; Kazuma generally remains indifferent to her attentions.

Her character background remains focused on her instructional duties, the romantic subplot, and her former pilot status. Familial details are minimal, limited to a single, non-substantive mention of her mother in dub credits.