Eryll is a Clavat girl suffering from "crystal sickness" in Final Fantasy Crystal Chronicles: Echoes of Time. She is Lian's little sister and lives in the same village as the Hero. Eryll is voiced by Ai Matayoshi in the Japanese version.
Early in the game, Eryll comes down with "crystal sickness", a sickness so rare that no one has the ingredients to make a cure. The Hero must find an experienced potion-brewer in order to cure her, and goes to Town for the first time to find someone who can concoct the medicine.
The Hero goes to the library on the advice of some townspeople and explains Eryll's sickness to Larkeicus, who tells the Hero that he knows how to make a cure, but requires a Buffasaur Horn first.
The Hero gets the Buffasaur Horn and gives the medicine to Eryll, who immediately feels better and rushes outside to play with Norschtalen. They are best friends, and Eryll affectionately and commonly refers to Norschtalen as "Norsy".
After the villagers disappear and only Eryll and Norschtalen are left, Eryll stands in front of the place where the crystal core was and places the shards back where they were when the Hero finds them. After all of the shards are replaced, Eryll becomes a spirit and runs into the Ruined Village.
It is revealed there that Eryll and all the villagers save the Hero, Sherlotta, and Norsy had died 2,000 years ago. Sherlotta was with Eryll when she died, and was then left alone and ran into the forest, leading to her connection with the Crystal Core.
Once all the villagers in their original bodies return to the Hero's village and they start disappearing, Eryll takes a little longer to become a spirit again.