Flora lives in a decaying house with 11,000 rooms. Her mother, a general, is rarely home. Her father, mostly insane, potters around in his room and occasionally emerges to destroy things. Her 14th birthday is approaching, and she is supposed to make a dress and write a speech for it, and then enter the army barracks for training, which she doesn't want to do.
One day, in a hurry, she foolishly takes an unreliable elevator in her house, and finds herself in a hidden library where she meets Valefor, her home's magical butler who has been banished by her mother. Resenting her mother, and the endless chores she has to do because of Valefor's banishment, she agrees to help him gain strength and return. But she doesn't know what she's getting herself into.