Scythe Riebaure is a member of the Brionac Force, and has a romantic relationship with his partner, Belial. He has the powers over the fabric of space, making him a formidable opponent. However, his special power is limited, and he must feed on her in order to restore his strength. He thinks highly of himself even on the battlefield, and seems to be proud of his status as a Crimson Noble, which is what he is perceived to be. He was voiced by Cam Clarke in the English release.
During the escape from Aerial Fortress Eulalia, he would confront Jude and his friends on the airstrip, and fought them in order to take back Yulie. Afterwards, Scythe explains that he plans to throw everyone but Yulie overboard, and in panic, Arnaud attempts to flee. He then proceeds to pursue, but is continuously blocked by Jude. Arnaud then hits the switches on the control panel that causes the planes to be shot out toward Scythe. In desperation, he uses his full power to try and escape, but likely due to the battle he is unable to, and is killed by the explosion caused by the colliding planes.
Posthumously, it is explained that he is not really a Crimson Noble, but a human with hematophilia who believed he was, and that his powers were actually due in part from drinking Belial's blood.