Hibiki Morishima trains as an apprentice healer at the Karasuma Voice Healing Center, specializing in voice medicine where song heals injuries and illnesses. Hailing from a rural farming family as the eldest of six siblings, this foundation informs her strong childcare skills and nurturing personality. She is known for her kindness, calm demeanor, and impressive cooking abilities.

Her family runs a small mixed farm in the countryside. Pursuing her healer training, Hibiki now lives in a rented room at the Karasuma clinic. The clinic's director, renowned healer Ria Karasuma, is a distant relative Hibiki has known since childhood. Hibiki developed an early love for singing, and encouragement from her elementary school music teacher influenced her decision to become a healer.

As a first-year apprentice alongside fellow high school students Kana Fujii and Reimi Itsushiro, Hibiki participates in clinic activities like cleaning duties, cultural festival preparations, and outdoor training camps. Her generally laid-back yet dependable nature shapes her healing approach; she is often seen supporting others during group treatments and daily tasks.

Hibiki shares a close connection with her family. Summers find her returning to her countryside home, where mentor Ria Karasuma visits. There, Hibiki maintains her role as the responsible older sister while continuing her training.

Throughout her apprenticeship, Hibiki works toward certification. She and her fellow apprentices eventually achieve C-rank healer status, an accomplishment followed by their unexpected expulsion from the Karasuma clinic, a development affecting their future paths.