Her origin was not clear, but given the fact that she was called 'onkata,' which meant she was a daughter of a daijin (minister), her father was believed to be FUJIWARA no Tadamasa, who was the Naidaijin (the Minister of the Interior) when Otsubone Court Lady of Jibukyo was a nyobo of Tokiko, and who had close relations with TAIRA no Kiyomori.
出自ははっきりしていないが、「御方」と敬称で呼ばれるのは大臣の娘である事から、治部卿局が時子の女房となった時期に内大臣の地位にあり、平清盛と縁の深い内大臣藤原忠雅が父親と考えられる。