Shirley is Rum's shadow master. She is reserved and rarely speaks, and doesn't share as close a bond with her living doll as other pairs do. She wears a white ribbon on her left index finger, matching Rum's black ribbon.
During the Debut arc's garden trial, a heartbroken Rum reveals to Emilico that Shirley hadn't even given her a name and that "Rum" is what she chose to call herself. At the end of the trial, Shirley is dubbed the weakest shadow and disintegrates while holding Rum's hand, right after the two had finally connected.
