Birthday
December 24
A bishop from the Barsburg Church, he convinces Teito to take the examination to enter the priesthood. The training he puts Teito through is vigorous and often involves his 'dolls', life-sized puppets he controls with Zaiphon. One of the 07-Ghosts, he is Fest. After Teito discovers that Castor and Frau are both one of the Seven Ghosts, Castor decides to wipe away Teito's memories of the incident, because their identities must remain a secret. Frau, however, stops him, telling him that if he takes away Teito's memories of when Frau revealed himself as Zehel, Teito will not remember Mikage's last smile (Frau transformed to save him when Mikage was possessed by Ayanami).

07 Ghost
Barsburg Empire's Military Academy is known for training elites who bring victory to the empire. Students of the academy freely utilize an ability called "Zaiphon" to fight, while the types of Zaiphon usable depends on the nature of the soldier. Teito Klein, a student at the academy, is one of the most promising soldiers produced. Although ridiculed by everyone for being a sklave (German for slave) with no memories of his past, he is befriended by a fellow student called Mikage. While preparing for the final exam, Teito uncovers a dark secret related to his past. When an attempt to assassinate Ayanami, a high-ranking official who killed his father, fails, Teito is locked away awaiting punishment. Only wanting the best for Teito, Mikage helps him escape. Teito ends up at the 7th District Church where he is taken in by the bishops. It is here that Teito attempts to evade the grasp of Ayanami and the Military, so he can rediscover his memories and learn why he is the person that can change the fate of the world.