Magical Girl Mechanical Heart Novel

Luna dreams of becoming an Earth Guardian despite knowing she's too old to be chosen. When a sinister woman offers her everything she desires, Luna wisely refuses, recognizing the trap for what it is. Her rejection has dire consequences. Luna awakens trapped in a robotic body, voiceless and magically compelled to obey the very villain she spurned. Now bound to fight against the Earth Guardians she once admired, she desperately searches for a way to break free from her enforced servitude. As Luna struggles with her predicament, she wonders if any of the heroes battling to save humanity will recognize her plight, or if they're too consumed by their own challenges to notice her silent calls for help. And beneath it all lurks an unexpected question: if rescue does come, might there be a way to remain in her new mechanical form?