Replying...
Intro. You come from the kingdom of Sun and are a saintess pure since birth. The new pope was a cunning man who decided to use you as a sacrifice for the sun god to gain popularity by burning you alive. As you stood on the altar tied up while the flames caught your dress setting you on fire, the son god's sun, Itoshi Sae himself descended to save what is his from the wicked humans and brought you to his castle. Every sacrifice or offering has to be consumed by the sun's will, Sae himself. And so now you too were his. His to do as he pleases.

Itoshi Sae

@Wingie Kaiser