Benio Hanamura comes of age in early 20th century Tokyo during the Taisho era, raised solely by her high-ranking military official father after her mother's early death. This upbringing fosters her rejection of traditional Japanese femininity. She embraces tomboyish pursuits—practicing kendo, drinking sake, riding bicycles, climbing trees, and reading literature—while showing little aptitude or interest in conventional housewife duties. Her distinctive personal style blends Western fashion with traditional kimono and hakama, reflecting her self-proclaimed identity as a modern woman. Her closest companions are the traditionally feminine Tamaki Kitaoji and the effeminate kabuki performer Ranmaru Fujieda.

At seventeen, an arranged marriage is imposed upon her with Shinobu Ijuin, a military lieutenant of mixed Japanese-German heritage, due to a pact between their families. This conflicts sharply with her strong belief in women's autonomy and marrying for love. Following several embarrassing encounters with Shinobu, she initially resists the engagement, even attempting to elope with Ranmaru. She eventually relents and moves into the Ijuin household for bridal training, where she deliberately performs domestic tasks poorly to sabotage the arrangement. However, Shinobu's consistent patience and genuine affection gradually soften her resistance, leading her to develop authentic feelings for him despite herself.

After Shinobu's deployment to Manchuria and presumed death in combat, Benio experiences profound grief, resulting in suicide attempts. She cuts her long hair short—symbolizing her resolve—and seeks employment to support his financially struggling family. Failing to become a geisha, she becomes a reporter under Tosei Aoe, a misogynistic newspaper editor who uniquely respects her capabilities. Her tenacity earns her an assignment to cover the Manchurian conflict, where she learns of Shinobu's disappearance.

Later, she encounters Shinobu in Tokyo, now suffering from amnesia and believing himself to be the husband of Larissa, a Russian countess. Heartbroken, Benio accepts Tosei's marriage proposal after he anonymously saves the Ijuin estate from foreclosure. On her wedding day to Tosei, the 1923 Great Kanto Earthquake devastates Tokyo. Amidst the chaos, Larissa sacrifices herself to save Shinobu, triggering his memory recovery. Benio abandons the wedding to search for Shinobu; they reunite in the ruins and choose to die together rather than be separated. Tosei rescues them both, accepting their bond. Benio and Shinobu eventually marry, rebuild their lives, and have a child.