|First Appearence:||The Tail of Emily Windnap|
|Appearences:|| The Castle in the Mist
Emily Windsnap and the Siren's Secret Emily Windsnap and the Land of the Midnight Sun
Millie is Emily's mom's friend. She cares about a lot of people. Millie is Emily's babysitter.Emily always calls her "Mystic Millie," because she's always using "magic" and "spells." She watches her favorite NBC shows on Wednesdays. Her boyfriend is a merman named Archie, but in Emily Windsnap and the Land of the Midnight Sun, she discovers that Archie is actually an evil spy for Neptune's traitorous twin brother, Njord. Archie loved Millie but got drugged and started hating her. He then used it as a cover to spy on Emily and her boyfriend Aaron.