It refers to a person who was the head of mandokoro keishi (officers in charge of the administration of the family affairs) of Sekkan-ke, which was also the head of Toshi choja (the head of Fujiwara clan), and its another name was shigyo keishi.
藤原氏一門の長である藤氏長者を兼ねていた摂関家の家政を掌握する政所家司の筆頭で執行家司（しぎょうけいし）の別名を持つ。