Princess Consort Elena gave birth to her legitimate eldest son Rien, who bore a sun-shaped birthmark on his back. Driven by ambition, her younger sister Vera secretly swapped the infant, leaving Elena wronged and forced to wander far from the kingdom.
Rien was taken in by Cedric, a retired knight living in seclusion among the mountains. He grew up alongside a young dragon and mastered extraordinary swordsmanship. When he came of age, he traveled to the royal city to join the knightly order. Together with his half-brother Cassian, he guarded the kingdom’s borders, yet his outstanding abilities made him a target of schemes that put him in mortal danger.
At the critical moment, the dragon that had stood by him since childhood rushed to his rescue. Riding the dragon, Rien returned to the capital, gradually uncovered all hidden truths, reunited with his mother, and saved the foster knight who raised him. With the dragon by his side, he quelled the palace unrest. In the end, he inherited the throne through his kindness and sense of duty, safeguarding a peaceful, stable life for all people of the realm.
