Tsuihou Ouji no Teii Dakkan

The Marb Empire is ruled by two pillars of power—the Emperor and the Pope. Ilha, born with the blood of both, is destined for greatness. But treachery strikes. His mother is slain, and Ilha is falsely accused, exiled, and enslaved. Ten years of suffering pass, until he crosses paths with Shio, a persecuted girl of the demon tribe. Shio's people were massacred by the empire, and her heart burns for revenge. Moved by Shio's unyielding fury, Ilha makes a choice—he will reclaim everything that was stolen from him. The time has come to rise, to fight, and to destroy the empire that cast him aside.

(Source: Shogakukan, translated)