Kyr is a 17-year-old soldier genetically engineered for peak physical performance. Living on Gaea Station, she is completely dedicated to the fascist military cause of avenging Earth's destruction. She possesses incredible combat skills and strictly follows the station's rules, making her an intimidating presence among her peers in the Sparrow mess. Her rigid adherence to duty often isolates her socially and masks her unacknowledged personal feelings.

Mags is Kyr's 17-year-old twin brother, a large and physically imposing young man belonging to the Coyote mess. Unlike his sister, he secretly harbors a strong aversion to violence and fighting, preferring peaceful simulations over combat scenarios. He feels alienated by Gaea Station's extreme militarism and rigid expectations, eventually deciding to reject his combat assignments to pursue a different path.

Avi is a brilliant, red-haired technician working in the Systems Wing of Gaea Station. He lacks the physical enhancements of the warbreed soldiers but compensates with extraordinary hacking and technological skills. He holds a deep-seated anger toward the forces that destroyed Earth and often expresses cynical, overconfident views. He provides crucial technical support to Mags and Kyr when they need to manipulate station systems.

Jole is the top authoritarian leader of Gaea Station, maintaining control over its surviving population through strict military discipline and propaganda. He is a genetically altered commando with an old war injury in his leg. As one of the original founders of the station following Earth's destruction, he acts as a paternalistic but ruthless figure who pits the younger generation against each other to maintain his grip on power.

Yiso is a young member of the majo zi species, an alien race possessing advanced reality-bending technology. They have pale silver eyes and a crest of fine white flukes that express their emotions. Naturally curious and talkative, Yiso provides Kyr with her first real interaction with the species she has been trained to view strictly as an enemy.

Cleo is a highly skilled soldier in the Sparrow mess with dark brown skin and tightly curling black hair. She is genetically modified for perfect hand-eye coordination rather than brute strength. She maintains a fierce, bitter rivalry with Kyr, resenting Kyr's exceptional training scores and the perceived favoritism she receives from Gaea Station's command.

Lisabel is a kind and exceptionally beautiful 17-year-old member of the Sparrow mess. Her appearance makes her the subject of station gossip, and her peers constantly worry about her inevitable assignment to the Nursery Wing, where women are expected to focus solely on reproduction. She offers a gentle, caring presence in opposition to the militaristic environment of Gaea Station.

Ursa is Kyr and Mags's older sister, living off-station on the ocean planet of Chrysothemis. Unlike her siblings, she was born naturally before their parents died. She has short hair, works as an armed historian, and lives a life free from the constant fear and rigid military discipline of Gaea Station. She hopes to reunite her family outside of Jole's authoritarian grasp.

Ally is a young boy living with his mother on the rainy, ocean-covered planet of Chrysothemis. He wears glasses, attends school, and enjoys doing art homework and fishing in the bay. He provides a sharp contrast to the militarized children raised on Gaea Station, showing Kyr what a normal childhood can look like.

Jeanne is a tall, red-haired warbreed belonging to the Sparrow mess. She is known among her peers for being exceptionally lean, deadly, and unflappably calm in high-pressure situations, earning her a swift assignment to a combat dreadnought.

Zen is a quiet, observant member of the Sparrow mess who is ultimately assigned to the Oikos Wing. She possesses sharp good sense and generally keeps to herself, preferring to avoid the intense rivalries that dominate the rest of her cohort.

Vic is a clever teenager in the Sparrow mess who has a deep fascination with the Suntracker systems. She maintains a secret romantic relationship with her messmate Arti, carefully hiding their connection from the strict authorities of Gaea Station.

Arti is a highly protective member of the Sparrow mess who actively seeks a combat assignment. She is fiercely dedicated to her secret girlfriend, Vic, and worries about how their different assignments will affect their hidden relationship.

Corporal Lin is a small, older woman with short iron-gray hair who oversees the Systems Wing. She walks with difficulty due to old war wounds sustained during the original uprising that led to Gaea Station's founding. She silently observes the activities of the younger generation.

Sergeant Harriman is a large, bald, older warbreed soldier who helps enforce discipline on Gaea Station. As one of the original hijackers who helped establish the station, he carries significant authority and military experience.

Admiral Russell is an older warbreed in his late sixties who serves as the second-highest-ranking officer on Gaea Station. Despite his public reputation for saving enemies during past conflicts, he actively enforces Jole's oppressive regime and uses his authority to make unwanted advances on younger women.

Sergeant Sif is a heavily pregnant, steely-eyed woman with a strong military build. She manages the difficult and oppressive conditions of the Nursery Wing, balancing her military duties with the physical demands placed upon the women assigned there.

Leru is an ancient majo zi and the current Prince of the Wisdom. Moving with slow, assured grace, they possess immense knowledge of the universe's reality-bending technology. Despite humanity's hatred toward their kind, Leru approaches human encounters with calm curiosity rather than fear.