The Demon Lord’s Contracted Princess

Princess Orianna of the Kingdom of Aurelion was exiled at eighteen for failing to detect any magical power, only to accidentally break the thousand-year seal of Lucifer, the King of the Demon Realm. She forms a life-bond with Lucifer, comes to know and love him, and successfully awakens her magic, becoming a powerful high-ranking mage. Returning to Aurelion, she finally defeats the step-queen Ivy, who had imprisoned the king, and Prince Sean, becoming the Queen of Aurelion.