Anna Atsuta (熱田杏南) is a high school student and classmate of Mayu Biwajima, serving as Mayu's close friend. Her personality is characterized as cheerful and energetic, often delivering sharp, comedic retorts, particularly in interactions with Nobunaga Oda.

Unlike other characters in the series, Anna possesses no historical connection to Oda Nobunaga. She is not depicted as a reincarnation, time traveler, or descendant of figures linked to the historical figure, establishing her as an ordinary individual within the story.

Physically, Anna has brown hair styled in braids or pigtails and green eyes, maintaining an appearance consistent with her status as a teenage girl.

Her role across official media remains consistently supportive, primarily interacting with Mayu Biwajima and providing comedic commentary. No character development, expanded backstory, or significant narrative arcs involving Anna Atsuta are documented.