Lala Hiyama is a human resident of the seed ship Sidonia who relies on a bear‑like life‑support suit to sustain her body. She was one of the original members of the Immortal Ship Committee, a select group of immortals who guide Sidonia, and served as a Garde pilot alongside Captain Kobayashi and the ace pilot Hiroki Saitou. Her deep bond with Hiroki led her to break with the committee after he opposed Kobayashi, and she subsequently withdrew from active committee duties. In the present day, Lala acts as the dorm mother for Sidonia’s cadets, managing the living quarters and offering maternal care to the young trainees. Her loyalty to Hiroki also motivates her to take a personal interest in the protagonist Nagate Tanikaze, whom she watches over and supports. She carries the scars of past battles, including a prosthetic arm, and retains the combat experience of a veteran pilot. Her personality is warm and gruff in equal measure, combining a no‑nonsense attitude with genuine concern for those under her charge. Despite her retirement from frontline service, she remains a steady, protective presence whose history and connections give her quiet influence aboard the ship.