Squall is a member of the Black Swan's Collective, after replacing Physic, and has the special ability as a Froster. She is currently the only female in the Collective and her disguise is to cover herself in head to toe in foggy ice. Her voice is described to be shaky and chattery, due to the fact that she is covered in ice and snow.
In Lodestar, it is discovered that she is Dex's mother, Juline Dizznee. She is often running away from the Collective's events or absent from them because she had to take care of her family. In Neverseen, she froze off Gethen's fingernails.
She joined the Black Swan just after the triplets were born because Physic was her doctor. Eventually Physic had to step down from the Collective and suggested Squall replace her.
Her age is unknown but is probably around the same as Edaline Ruewen, her sister.