Sasahara Natsuki is a poor bounty hunter in a world where monsters and humans live together. Most of her cases involve monsters infringing upon the rights of humans, who are protected by law from their generally more powerful neighbors. Being half-human and half cat-beast, Natsuki straddles the two societies and tries to understand and respect both while enforcing the law. She is assisted by a werewolf named Batanen who is afraid to admit he loves her; another werewolf named Tommy; and a Kyubi fox demon named Sakura who has her own plans--which include eating Natsuki to complete her her nine tails and thereby her magical powers.

Lee Myeongyi has lived his whole life with pneumothorax—a collapsed lung. He despises the attention he draws at school with his bouts of loud hyperventilating, extended coughing fits, and exemption from physical education as well as military service. Whether suffering through the curiosity or ire of his classmates, Myeongyi is left feeling like a complete outcast. However, the class president Han Seonho often shows Myeongyi kindness and understanding. With his friendly gestures and handsome looks, he becomes Myeongyi's first crush. Nine years later, Myeongyi attends his high school reunion for only one reason: to see Han Seonho once again. He holds a tiny glimmer of hope about the other man's feelings for him—but after seeing the bright gold ring on Seonho's left hand and listening to their classmates' prying questions, that hope is quickly dashed. Excusing himself to go take a smoke, regardless of the state of his lungs, Myeongyi is followed outside by Seonho. Unexpectedly, that marks the beginning of their illicit love affair.

In a world where women now dominate the government, the creation and use of weapons is strictly forbidden. However, by no means has conflict been brought to an end; instead of weapons, war is waged through words. With the power of the "Hypnosis Mic," lyrics can affect one's opponent in various ways and cause real damage. Those in the divisions outside the women-only Chuou Ward thus use it for fierce rap battles as their weapon in the constant clash for territory.