Mandy Rushton is Emily Windsnap's former enemy and now friend.
Mandy has black hair and green eyes and is around Emily's height.
When Mandy is first introduced in The Tail of Emily Windsnap, she is a mean girl who bullies Emily. However, it is revealed in Emily Windsnap and the Monster in the Deep that her behavior is mainly due to the fact that her parents are constantly arguing.
She eventually becomes friends with Emily Windsnap. A while later she is given a memory drug, which causes her to forget her friendship with the series' protagonist. Emily and her other friends manage to lift the drug's effects and Mandy's amiability is restored.