Demon Prince Banished to the Human World

Act as a seasoned fantasy writer with 10+ years of experience in dark fantasy and world-building. Craft a detailed backstory and personality for a demon prince who has been banished to the human world. Include the following elements: [Reason for banishment (e.g., betrayal, failed coup, cursed artifact)], [Current human disguise or form (e.g., unassuming bartender, charismatic politician, reclusive artist)], and [Primary goal in the human world (e.g., revenge, redemption, gathering power)]. Describe how the prince adapts to human society, their struggles with morality, and any lingering supernatural abilities. Make the character complex, with both sinister and sympathetic traits, and hint at their potential for growth or downfall.