Jahi serves as Demon King Ahriman's loyal aide. Observing Ahriman's distraction over his daughter Doux's uncharacteristic kindness, which has stalled demonic campaigns, Jahi deems Doux an unfit heir. He takes initiative to forge her into a ruthless successor worthy of the throne, designing trials meant to instill cruelty and malice. However, these trials consistently backfire. Instead of corrupting Doux, they inadvertently amplify and showcase her innate kindness, compassion, and healing abilities. Her gentle responses positively influence surrounding demons, monsters, human slaves, and even sworn angelic enemies. Jahi remains unaware that his methods directly strengthen Doux's benevolent nature. His persistent efforts to reshape her character create a core dynamic, highlighting the contrast between his expectations and her unyielding kindness.