Mayor Taisha is a figure who appears at the outset of the story as the leader of the Mud Whale, the floating island community that serves as the setting. She became the chieftain of the Mud Whale sixteen years before the events of the narrative, assuming the role at the age of forty-two. Her background places her among the unmarked members of the society, meaning she does not possess the thymia power that the marked individuals wield. This lack of personal power influences her position and her relationship with the governing elders, who often treat her as a ceremonial figure rather than an autonomous leader.

In terms of personality, Taisha is portrayed as deeply kind and caring toward all the inhabitants of the Mud Whale. She holds a genuine love for the community and its unique way of life, yet she harbors a subtle resentment for the way the elders reduce her to a mere doll figure, used for their own purposes. This internal conflict between her affection for her people and her frustration with her constrained role shapes her motivations. She desires to protect the Mud Whale and its people, but she often struggles against the decisions made by the elders, who hold the real authority.

Her role in the story is that of a supportive authority figure who provides guidance and stability, especially during the early crises that the Mud Whale faces. She interacts closely with the main characters, including Chakuro and the moles, and serves as a bridge between the youthful energy of the marked individuals and the rigid traditions upheld by the elders. Her key relationships include her bond with the people she governs, her tense dynamic with the elders, and her paternal or maternal care for the younger generation, whom she encourages to seek their own futures.

Throughout the series, Taisha undergoes development as she becomes more assertive and begins to challenge the elders’ control. She learns to trust the younger characters and to let go of the fear that has kept her passive, ultimately finding a stronger sense of her own will. In terms of notable abilities, Taisha is not a user of thymia; her strengths lie in her diplomatic skills, her emotional intelligence, and her resilience as a leader. She is capable of making difficult decisions for the greater good, even when those decisions conflict with her personal feelings. Her wisdom and experience make her an essential stabilizing force on the Mud Whale, even as the world around her changes dramatically.