勇者で親友のユーノ、僧侶で恋人のイリーナ……。勇者パーティのメンバーは皆、かけがえのない仲間だと、魔法使いのクロムは信じていた―――だが、それは間違いだった。クロムはパーティを強化するための「生贄」として捧げられてしまったのだ!恋人に裏切られ、魔力すべてを奪いとられ、パーティを追放されてしまったクロムに残されたもの、それは『闇』だけだった。さあ、復讐を始めよう──。
Chrome was a magician in the hero’s party. He fought the Demon Lord’s army alongside people like Irina, the lover who vowed to marry him in the future, and the hero, Yuno, who was his close friend. They were all close companions. However, that was only in Chrome’s mind. His lover, Irina, became intimate with the hero, Yuno, and Chrome was sacrificed to make the hero stronger. Chrome’s magic powers were snatched away and he was kicked out of the party. Demons surrounded him as he was on the verge of death and he was driven to a corner. At that moment, Chrome awakened to a “darkness” within himself. Amidst his despair, he acquired an unrivaled skill. Now with this skill, he could exact revenge.