Hailing from the Snow Kingdom, Coffret serves directly as Princess Snow White's fairy companion. This fairy witnessed the villain Gelos freeze the kingdom. Amidst the assault, Coffret fled to the human world clutching Princess Snow White's prized ring, seeking champions to save the realm. The fairy tirelessly scoured for potential rescuers.

Upon finding the Tropical-Rouge! Pretty Cure team, Coffret revealed the kingdom's icy imprisonment and the princess's capture. Presenting the royal ring, the fairy declared it essential for restoring both land and people. Coffret then guided the Cures to the Snow Kingdom.

Inside the frozen domain, Coffret steadfastly supported the team—offering rallying words, sharing intelligence on the kingdom's suffering and the princess's status, and aiding the Cures to awaken the ring's latent power at critical junctures.

Once Gelos fell and the Snow Kingdom thawed, Coffret remained by Princess Snow White's side. The fairy participated in the realm's rebuilding alongside the princess and conveyed heartfelt appreciation to the Cures for their decisive aid.