Who is Mallie, Mamzell from Anecdotes of Destiny ; and, Ehrengard and what is their importance?

Malli is the daughter of Madam Ross and Captain Alexander Ross. Over time, Malli decides that acting in the theatre is preferrable even to her own life. In the end, she leaves her home, her fiance, and her past to continue to playing Ariel in the theater troupe's play, The Tempest.