Sierra

Japanese name:

シエラ

Sierra is an anime-only character. She is Presea's identical twin sister, and the only way to tell them apart is by the feather-shaped birthmark on Sierra's chest (first noted by Caldina when all the girls are bathing together). She makes her appearance throughout the anime's second season, corresponding with Presea's presence in the manga. Sierra is pretending to be Presea to take away some pain of the Magic Knights, who blame themselves for not being able to help Presea, and of Ascot, who blames himself for killing Presea. Clef falsely tells the Magic Knights that Princess Emeraude made a wish to revive all the people who died while she was imprisoned, but in fact, no one can revive a life once it is lost.

Sierra is in love with Clef, as was Presea, though her love is one sided (Alcyone confirms this after learning of Seirra's true identity). She cannot make weapons out of Escudo, but she can help revive the weapons once they are lost; she did this to help Hikaru regain her sword after Nova broke it.

She is named after the Ford Sierra.

Wikipedia