In Slave's Sword: The Free City, Luna of Maldonia finds herself morally offended by the actions of her own empire. That's why she abandoned her status and everything that came with it to live in the free city of Selway. Now Luna lives a peaceful life as a mercenary. However, she finds herself embroiled in a situation that leaves her being a slave. Can Luna somehow find the strength to escape this hell hole like she did when leaving her empire? Everything is on the line because Luna no longer has her freedom, and she no longer has her status in the empire that she once belonged to.