Despite having the ability to see otherworldly creatures, Chise Hatori has never considered herself lucky. Ever since her parents abandoned her at a young age, it has been the center of her hardship, driving her to the point of selling herself to the slave market, just to secure a place she can call home.

Presented to the bidders as a rare "Sleigh Beggy"—beings who have an unusually high affinity to magical energies—Chise's last remaining hope appears in the form of Elias Ainsworth, a mysterious magus more beast than man. Rather than keep her as a slave, he has decided to make her his apprentice, as well as his bride.

Chise is not only physically transported to the English countryside where Elias lives, but also introduced to a world where wondrous things such as fairies and dragons are the norm. But she soon realizes there is as much to fear in her new life as there is to marvel at. And lying at the heart of it all is the question of whether she has fallen into the hands of something much darker than her own inner demons.