Rosemary was born into royalty, yet unlike the princesses in fairy tales, she does not relish the privileges that come with her title. Instead, she faces disdain from those around her for failing to meet her society's expectations of the Kuroriku clan's main family: strength, resilience, and vitality. Rosemary was born with a delicate constitution and limited mana, unlike her family members who possess robust bodies and immense potential.
The only ones who treat her kindly are her brother and his girlfriend, Artemia. Despite their support, Rosemary yearns to escape her unloving father and the people who make her life unbearable. One day, an opportunity arises in the form of a tall, dark, and handsome knight with a cold gaze. Will she accept this chance, even if it means entering a loveless marriage? Or could love unexpectedly blossom in the most unlikely of places? Is that only something that happens in fairy tales?