Tamaki Kitakoji is Benio Hanamura's best friend, defined by her traditionally feminine demeanor in contrast to Benio's tomboyish nature. She shares Benio's passion for women's rights, deeply inspired by the feminist publication *Seito* magazine and its founder Raicho Hiratsuka's declaration: "In the beginning, woman was the sun. Now she is the moon. We must become a new woman." Tamaki's initial romantic feelings for Shinobu Ijuin contribute to Benio's reluctance regarding her own arranged marriage to him.

Her journey sees a shift from conventional aspirations toward progressive ideals. She evolves from adhering to traditional expectations to pursuing personal fulfillment, ultimately forming a romantic bond with Shingo Onijima, a military figure known as "The Black Wolf of the Manchurian Steppe." Despite Shingo's traumatic past, including the childhood loss of his left eye, Tamaki chooses to follow him to Manchuria, placing her emotional commitment above societal norms.

Visually, Tamaki embodies Taisho-era refinement, often depicted with the "Ojou Ringlets" hairstyle and elegant attire. Her relationship with Shingo creates a secondary romantic narrative paralleling Benio and Shinobu's story, unfolding amid historical upheavals like the Great Kanto Earthquake and highlighting themes of loyalty and resilience.