The character known as "Mother" is first encountered by protagonist Nayuta during her walk home from school. Frail and visibly near death, Mother urgently requires medical aid, prompting Nayuta to escort her and her young son, Kiro, to a hospital. Though she survives emergency surgery, Mother vanishes without a trace shortly after the procedure, her absence unexplained.

Her disappearance leaves Kiro reliant on Nayuta, drawing her into conflicts surrounding the Jarun—a golden tiara-like artifact linked to psychic powers—and the hidden dangers it attracts. Mother’s sudden exit intertwines with escalating tensions involving unseen forces, looming extraterrestrial threats, and Nayuta’s awakening abilities as an esper. The unresolved mystery of Mother’s fate persists as a pivotal thread within these unfolding events.