The previous Princess Melloblum had exhausted herself for her people’s happiness—a sacrifice that haunted the former First Lethal Thorn with guilt. So it trained its apprentice to become the perfect guardian: one who could detect and eliminate any danger to the princess without hesitation. But years later, it realized its mistake. "Thorns hardened by tears grow unyielding, yet lose their scent." A First Lethal Thorn that knew nothing of joy could only bring sorrow to those it sought to protect.