Originally only known as "Father" to Teito, he took Teito into a church and raised him. When Teito was a child, he taught him many things, including the majority of the church's writings. Fia Kreuz was excommunicated from the Church shortly after Teito left, for escaping with Pandora's Box. He cared for Teito very much, having raised him and being his primary father figure. He is actually the King's younger brother, making him Teito's blood uncle. Although there are many differences between him and Frau, Teito is still reminded of Kreuz a lot when Frau is being serious. Fia Kreuz is also another of the 07-Ghosts, Vertrag.
