Emma

Emma was a nonmagical serving girl who worked for Joseph Albright's family in approximately the 1520s.

Background
Emma was the daughter of a family who worked as servants on the Albright estate, and was assigned to their heir Joseph as a caretaker. The two of them grew to be friends and regularly played chess. Initially Joseph always won; however, Emma was determined to improve and sought advice from the adults of the house, and eventually she defeated him. However, when Joseph told his parents about her victory the next morning, they punished him with a pain curse followed by a severe beating lasting most of a day. He discovered afterwards that Emma had fared much worse: to erase the perceived shame of their heir's defeat, they had murdered her along with her entire family.

Trivia

 * Joseph's servant was unnamed in the light novel and was only described in exposition. The manga depicts her but doesn't name her. A flashback in episode 1x11 of the anime names the character "Emma".