Nuala is presented as a gift to Dream from Faerie during the events of Season of Mists. She appears initially as a beautiful blonde woman, but that appearance was the result of a faerie glamour. When Dream removes the glamour, her true appearance — a small, brown-haired, plain-looking girl — is revealed.
When she leaves, Dream grants her a boon as a reward for her years of service, allowing her to call on him if she needs to. Nuala had been nursing a crush on Dream for some time, so she finally calls him, asking him to love her. Dream is unable to do this, but he says that he can at least "send you a dream of my love." Nuala responds, "I already have that, my lord."
She subsequently appears in the Sandman spinoff series, The Dreaming.