Charlotte is the princess and heir of Phlaburg. Kidnapped by bandits and abandoned in a remote cabin, she was rescued by Cain Asbell, a young shepherd who located her with help from a freed fairy, Elise. As reward for her rescue, Charlotte's family grants Cain lordship over Norland and offers her hand in marriage, conditional upon him elevating Norland to the kingdom's most prosperous territory within five years, establishing the narrative's core political and romantic stakes.

Charlotte actively observes Cain's governance and the rivalry between Norland and Tedmond. Her marital future is contractually tied to whichever lord rules the strongest territory after five years. She possesses blonde hair and royal status.

Demonstrating agency, Charlotte adopts the secret identity of "The Mysterious Masked Warrior," a magical-girl parody. She challenges the swordswoman Tsubaki to a duel. Though defeated, her intervention indirectly inspires Cain to later defeat Tsubaki. This act highlights her willingness to covertly influence events despite her official role as a political figurehead.

The narrative concludes with Cain securing Norland's supremacy and defeating his rival, Francis of Tedmond. Charlotte fulfills the marriage agreement, wedding Cain and cementing his rise from shepherd to king.