This story takes place in a world shaped by ancient dragons and enduring legends, where multiple young figures are born into the same era but raised in vastly different lands. At the northern frontier of the Valen Empire stands House Castus, an old and honorable lineage bound by duty, sacrifice, and an unbreakable vow to defend the realm from barbarian hordes and legendary beasts beyond the mountains. Yet the world does not revolve around a single family. Within the empire, ambitious nobles scheme in silence, while rival empires, desert principalities, independent kingdoms, and barbarian federations all pursue their own visions of power, unity, or survival. As the balance between sword masters and scholars of magic begins to shift, long-dormant myths and ancient forces start to awaken. This is not the tale of one hero alone, but the chronicle of a new age—where legacies collide, oaths are tested, and the fate of the world is forged by many hands.