In a world where monsters and humans coexist, Sasahara Natsuki works as a bounty hunter struggling to make ends meet. Her assignments usually involve monsters who have violated human rights, and as someone who is half-human and half-cat-beast, she is uniquely positioned to navigate between the two societies despite their inherent differences. Though she strives to enforce the law while respecting both sides, Natsuki has to contend with a number of challenges, including Batanen, a werewolf who harbors secret feelings for her, Tommy, another werewolf who assists her, and Sakura, a Kyubi fox demon with a sly agenda. Sakura desires to devour Natsuki to increase her power, since Natsuki's nine tails are not yet fully formed.