Sisters

Rosette has trouble getting her brother back. He has taken horns, from a talking bird (Aion), that belonged to Chrono, but they were ripped off his head by Aion. Now Joshua is being controled by them and does not remember what his sister, Rosette, looks like. He is an Apostle of hope, an angel with magical powers, and was sick when he was just a boy. But as Joshua grew up with the horns in his head, he does not realize the terrible things he has done to the earth. It is all caused by Aions lies and Joshuas servant, Florette/Fiore Harvenheit, a young girl who is a jewel sommoner like her sister:

Satella Harvenheit  who has been searching for her for years. Before Aion had taken her and drained her blood, but her powers remained, and kept her as a slave. Now she cares for Joshua and also serves for Aion. Rosette is determined to get the earth safe, even knowing her life is going to end soon enough.