Their account names are always left empty, so they're only known as "Blank"
This article is referring to something that does not have an official name. It is a fan-given name for the substitute lack-thereof, the name is either an alias, surname or nickname. You can help No Game No Life Wiki by expanding it!
While her name is unknown, she is the second person Sora and Shiro play a game against. After losing to Sora, she left distraught and surprised. She has a pyroxene, a special mineral, around her neck. In the light novel and manga, her character is replaced by a middle-aged man playing the siblings instead.