Born as a Leonin—a rare, cat-like race of magical beings—Joy spent her earliest years completely separated from her kind. Abandoned in the bustling streets of Lumina City, the capital of the Moniyan Empire, she was taken in by a kind-hearted, impoverished old woman. Under her adoptive grandmother's warmth, Joy grew up with a happy heart, shielded from the harsh realities of the world.

Her innocent existence shattered when her aging grandmother fell deeply ill and passed away, leaving her utterly alone. To survive the unforgiving city streets, the young Leonin had to weaponise her supernatural agility, transforming into Lumina City’s most notorious "petty thief" just to steal food and fill her empty stomach. For years, she evaded the empire's guards, living a life of bitter isolation where her only desires were to find her true identity, satisfy her hunger, and experience warmth once again.

Her past and destiny caught up with her during a fortunate turn of events that led her away from the cold alleyways of the human empire and back to the Azrya Woodlands, the ancestral home of her people. Expecting rejection, she was instead welcomed with open arms by the Leonin tribe, whose simple, pure, and unconditional love instantly mended her fractured, wandering heart. It was within this safe haven that Joy discovered her unique spiritual affinity for rhythm and music, awakening a dormant power.

No longer afraid of being abandoned or losing the people she loves, Joy chose to trade her life as a runaway thief for that of a proud guardian. Harnessing the magic of her ancestors, she transformed her rhythmic energy into a formidable weapon, vowing to defend her newfound kin from any outside threats. Today, she roams the borders of her homeland as the Flash of Miracle, a streak of golden lightning ready to strike down the dark forces that dare threaten the peace of her family.