Yetu is a 34-year-old wajinru who serves as the society's historian, an official duty she took on at age 14. She is a highly sensitive creature required to hold 600 years of traumatic collective memories so her people can live in blissful ignorance. The immense psychological and physical weight of this history leaves her socially isolated and deeply resentful of the community she must serve.

Amaba is Yetu's mother and a typical wajinru, biologically predisposed to forgetfulness. This lack of memory prevents her from retaining the context of past arguments with her daughter, causing them to repeat the same painful conflicts. She focuses entirely on the present and insists that Yetu fulfill her duties, failing to grasp the severe emotional toll the role inflicts on her child.

Oori is a stoic and resilient two-leg (human) woman who forms a profound bond with Yetu. Having lost her own homeland to devastation, she approaches life with a hard exterior and resists intimate connections to protect herself from further grief. Despite her sharp boundaries, she helps Yetu articulate personal needs outside of societal duty.

Zoti Aleyu is the first historian and queen of the deep. Originally an isolated "strange fish" who learns language from a human, Zoti takes on the responsibility of organizing their kind into a protective underwater society. Recognizing the traumatic origins of their people, Zoti decides to absorb the collective suffering, establishing the role of the historian to keep others safe from painful truths.

At nearly 150 years old, Nnenyo is the oldest living wajinru. Because of his advanced age, he retains more memories than the rest of the community, allowing him to empathize with Yetu's position. He acts as her care-maid and a surrogate parent, gently shielding her delicate constitution from loud noises and overwhelming interactions.

Suka is a kind two-leg woman who discovers Yetu washed ashore after the historian flees the ocean. She acts as a patient healer, tending to Yetu's injuries and providing her with nourishment. Through their conversations, Suka shares basic information about surface life and facilitates Yetu's introduction to Oori.

Waj is a two-leg woman who plays a foundational role in the wajinru origin story. After surviving a ship crossing, she encounters the early sea-dwellers, teaching them language and naming them "zoti aleyu." Her eventual departure to build a raft and return to her homeland instills a profound sense of abandonment in the creatures she leaves behind.

Basha is a past historian who holds a drastically different perspective from his predecessors and successors. Instead of sorrow, the memories of violence committed by the two-legs fill him with a righteous, burning anger. He believes that pain is fundamental to the wajinru identity and uses his influence to channel his people's energy into vengeance.

Aj is the first wajinru pup witnessed being born directly from the tragedies of the slave ships. Delivered by Zoti's teeth, he represents a grim new beginning for the zoti aleyu. He eventually grows up to become a leader and the second historian, following Zoti's precedent of withholding painful history from the general population.

Omju is a conservative leader among the wajinru during Basha's time as historian. He organizes a governing council that prioritizes tradition and safety, preferring to keep the wajinru hidden from the two-legs. His cautious inaction puts him in direct opposition to Basha's militant desire for justice.

Ephras is a wajinru from the past who suffers severe injuries at the hands of the two-legs. His suffering serves as a primary catalyst for Basha's righteous rage, pushing the historian to abandon peaceful isolation in favor of open conflict against surface dwellers.

Kata is the youngest child of Nnenyo. During the preparations for the Remembrance, Kata gifts Yetu a comb used by one of the wajinru foremothers, providing the weary historian with a rare, comforting moment of connection to a specific child ancestor.