Josephine Greengrass, more commonly known as Josie was a simple pure-blood girl in Slytherin house having to keep a brave face while she heard terrible things being spoken about others. Sirius Black was also a pure-blood boy who became the first member of the black family to be in Gryffindor. Now.. as we typically tell the story, when he's fifteen he runs away to the potters but not in mine.