Qven is a non-human juvenile created by the mysterious alien Presger. Raised in a strict, collective environment with little personal autonomy, e is preparing for an eventual biological merge known as a "match." Qven develops a strong desire for personal autonomy after witnessing a disturbing match between other juveniles.

Reet is a 30-year-old pipeway worker living in the Zeosen System. He is an adopted member of the Chirra ethnic group who harbors secret, violent urges that he suppresses. When a local leader suggests he might belong to a lost aristocratic family, Reet begins searching for his true biological identity.

Enae is a 56-year-old human who spent most of hir adult life caring for an overbearing grandmother. After being left with only a modest allowance, sie accepts a busywork assignment as a Special Investigator for the Radch Office of Diplomacy. Hir task is to track down a 200-year-old missing fugitive.

Dlar is an adult Presger Translator overseeing juvenile development. They hold significant authority over Qven and demand strict adherence to their clade's expectations. Dlar serves as a representative of the rigid structures limiting individual autonomy among the Translators.

Seimet is a high-ranking Radchaai official overseeing the fragile treaty between humanity and the Presger. She is deeply invested in maintaining Radch political dominance and preventing other groups from gaining legal recognition.

Mr. Nadkal is a leader within the Siblings of Hikipu, a group resisting oppression from the Phen people. He contacts Reet with a theory about Reet's genetics, hoping to install him as a symbolic figurehead for the Hikipi cause.

Tzam is a juvenile Presger Translator growing up alongside Qven. They feign camaraderie by proposing an escape plan, masking their true intentions regarding the matching process.

Teacher is an adult Presger Translator assigned to watch over Qven. They provide instruction on biology, genetics, and expected societal roles while maintaining a strict daily regimen for the juveniles.

Istver, whom Reet calls Mom, is one of Reet's three adoptive parents. She belongs to the marginalized Chirra ethnic group and provides Reet with unconditional emotional support as he investigates his heritage.

Echemin, whom Reet calls Nana, is another of his adoptive parents. E has an abrasive communication style but remains fiercely protective of Reet's well-being and legal rights.

Maman is the third of Reet's adoptive parents. Along with Istver and Echemin, she helped raise Reet on Rurusk Station and supports his search for identity.

Grandmaman is Enae's recently deceased grandmother. She was a controlling guardian who restricted Enae's freedom and quietly sold off the family estate to settle debts without telling hir.

Zemil is the woman who purchased Grandmaman's estate and was legally made her heir. She provides Enae with a diplomatic assignment effectively removing hir from the property.

Caphing is Zemil's cousin and Enae's job supervisor. The two bond over coffee before Enae departs, providing Enae with a rare sense of genuine familial connection.

Ideni is a militant member of the Hikipi resistance working alongside Mr. Nadkal. She holds radical views and believes violence is necessary to combat Phen oppression.

Sphene is a sentient artificial intelligence representing the Republic of Two Systems. Her consciousness typically inhabits an ancillary body. She attends diplomatic meetings to advocate for AI rights under the Presger Treaty.

Batonen is a human treaty jurist from outside the Radch Empire. She uses a mobility chair suited for low-gravity environments and advocates for inclusive legal definitions of humanity.

Agagag is an ambassador representing the amphibious Geck species. She attends diplomatic meetings remotely by piloting a multi-legged biological mech suit.

Tibanvori is the human ambassador assigned to interact with the Geck species. She attends council meetings to ensure Geck perspectives are accurately represented in human space.