Life for Valeriana Kerrigan has recently taken bad turns; her father dies, her best friend leaves and her mother is fighting to keep their life together. But in spite of all the imperfections, there are upsides. She gets accepted into the university of her first choice and is walking down a path of her dreams.
Until, of course, everything is upended when she encounters a sword-wielding woman in a local alley who saves her skin from the claws of a demon. She is then removed from her peaceful life and thrust into a world wholly different from the one she's grown used to knowing. By fortuitous encounters, she finds herself joining an elite circle of students in Celeste Academy to train as a knight-all to make sure that their pest troubles does not infect her world.