Asa Kato is a tomboyish, aggressive, and stubborn teenage girl who operates aboard the flying battleship Amanohara during the 1904 Russo-Japanese War as a member of the Lime Unit, a group wielding supernatural Konjiri powers. Her stern, disciplined demeanor was forged by a military upbringing under her father, along with years of kendo practice and a deliberate rejection of traditionally feminine mannerisms. She frequently clashes with Sarasa Honda, whose flamboyant, Western-influenced behavior grates against Asa’s no-nonsense worldview. A deep loyalty marks her past: she shared a close bond with the late Lieutenant Commander Masanosuke Date, whom she regarded as an older brother and regularly practiced kendo with. His sacrificial death left an indelible mark, amplifying her drive to protect others while burying her grief beneath a brusque exterior. In combat, she pilots the green unmanned mecha Kiyomasa with calculated ferocity, wielding a staff and channeling plant-based abilities. Though relentless in battle, she shows fleeting cracks of concern, especially toward timid unit member Kinu Fukushima, even if her blunt approach sometimes reduces Kinu to tears. Asa remains notably private compared to her peers; unlike the rest of the Lime Unit, her nudity or undergarments are never exposed to their commander, Shintaro Umakai. Her narrative arc focuses on reconciling military rigidity with the complexities of camaraderie, as she gradually accepts new leadership and navigates emotional vulnerability.