Esmeralda Greenmoon

Home town: Tearmoon Empire

The eldest daughter of the Duke of Greenmoon. Although she claims to be Mia's best friend, she is not trusted at all by Mia in the timeline of the main story because in the previous timeline she abandoned her homeland as soon as the revolution broke out and fled the country.

(Spoiler from Volume 4 of the LN) In fact, her friendship to Mia is true. The escape in the previous timeline was made by her father, not by her will.