An older mail-rider with short orange hair, who is always seen with Hilda and Chris. Due to Ange being directly responsible for Zola's death, she resents the fallen princess and tries to get revenge by ridiculing her constantly, however, much to her chagrin, Ange manages to exact revenge on her. She, together with Hilda and Chris engage in a form of ménage à trois in Zola's room which is now owned by Hilda.
After she and the rest of the unit are saved by Ange from a new and very powerful dragon, she finally accepts and befriends Ange. Upon learning that Hilda was simply using her, Chris, and Zola as a means of achieving her goals, Rosalie becomes increasingly resentful towards her during her abandonment. They later make amends when Julio and his army invade Arzenal. She has feelings for Chris and wants to rescue her from Embryo.