Natsu Aoi is a supporting character from the anime Labyrinth of Flames. She is a Japanese princess who lives in Russia, and she is the girlfriend of the main protagonist, Galan. Her family background is that of Japanese emigrants, and she is the successor of that family line. Natsu is the catalyst for the story: she gifts Galan an ancient sword, which triggers a series of strange events and attacks, leading the characters into a forgotten kingdom.

In terms of personality, Natsu initially comes across as a kind, gentle, and composed young woman. She appears to be a caring and supportive partner to Galan. However, she also possesses a darker side that becomes apparent, particularly in relation to her father, Shigemitsu Aoi, who is portrayed as overly intrusive and perverse. Her reactions to her father’s behavior reveal a more frustrated and sharp-edged aspect of her character. Natsu’s motivations are closely tied to her relationship with Galan; she wants to help him achieve his dream of becoming a samurai, which is why she gives him the sword. Her role in the story is that of a supporting figure who sets the adventure in motion and accompanies Galan and the other characters through the comedic and chaotic events.

Natsu’s key relationships include her romantic bond with Galan, which is central to her actions, and her difficult dynamic with her father, Shigemitsu, who is a source of comedic conflict. She also interacts with the other female characters who join the journey, though her individual relationships with them are not deeply explored. Over the course of the two-episode OVA, Natsu does not undergo significant development; she remains a steady presence who helps drive the plot forward. She does not demonstrate any notable supernatural or combat abilities, relying instead on her personal connections to influence events.