Peter, a youth of mixed heritage, suffers bullying by his clan due to his impure bloodline and endures the humiliation of having his engagement publicly annulled. At his lowest ebb, he forms a pact with a succubus dwelling within an ancient magic ring. Empowered by this bond, he stages a dramatic turnaround and gains admission to a prestigious magic academy; however, his identity as a half-demon is exposed, marking him as a target for extermination by the Holy See. Caught between loved ones and sworn enemies, Peter faces a crucial choice: bow to fate, or—as a half-demon—declare war on the entire corrupt world of the Holy Light?