From Turtle Paradise :

"In the world of man, there lived two men who had claimed to be King, however, as if declared unfit for the role, the two perished on the same day. Leaving in their wake were two children, both of whom were called ‘Prince’… And now, the wheels of fate have begun to turn for those two..”
Sasagi, the cursed prince who is being slowly and painfully consumed by the dragon blood within him, and the prince Shida, whose life has been doomed to a farce…. Will their meeting be enough to restore the balance of the world?