Kota, a sorceress who works as a detective with the Grimmani Detective Agency, is on her way to a new posting on the world of Proximus. She’s been charged with transporting a mystical artifact called a Keystone that will allow Proximus to build a magical gateway back to Kota’s homeworld of Emake Maa. When the Aethership transporting Kota is attacked by pirates, Kota helps fight them off, and finds herself taking care of a half demon woman, Nadani who was being held as a slave on the pirate ship.
When Kota and Nadani arrive on Proximus, Kota is injured in an attempted assassination, and finds herself embroiled in a plot involving cultists who want her dead for some reason. Kota begins to dig into the motives of the assassin while trying to navigate her growing feelings for Nadani. Something made all the harder by more attempts on her life and the emotional minefield that Nadani’s past as a slave left behind.
When Kota learns that the assassins may be after Nadani as well, she becomes desperate to learn what they want. Something that puts her on a collision course with a cult that wants to use Nadani and the Keystone to open a permanent gateway to hell itself.