Lieutenant Marc 1er Juin serves in the Imperial Japanese Army with partial German heritage. A pre-birth arranged marriage pact binds him to Benio Hanamura, though their initial encounters are contentious. During a critical confrontation, he compassionately releases Benio from their engagement to ease her friend Tamaki’s distress, as Tamaki harbors feelings for him. This act enables Benio to pursue a relationship with Tosei Aoe.

Military deployment to Siberia results in Marc being presumed dead after an explosion. Rescued by Russian woman Larissa, he survives and recovers under her care. Trauma-induced amnesia leads him to adopt the identity of Larissa’s deceased husband, living anew in Russia. He eventually returns to Japan with Larissa, unaware of his past.

During the Great Kantō earthquake, Larissa dies shielding Marc from debris. Her final words reveal his amnesia and urge reconciliation with Benio. Marc plans to leave Japan alone, believing Benio moved on with Tosei. Benio intervenes during another tremor, declaring she would rather die together than face separation again. Tosei rescues them both from peril.

Marc and Benio reunite and marry, concluding their prolonged journey. His military background, disappearance, Siberian survival, and return form a consistent narrative arc across adaptations. The anime compresses the reunion timeline due to production constraints, while later films extend the storyline to incorporate more detailed resolution elements from the source material.