Senge Kunimaro is the eldest son of Senge Takamasa, the head priest of the Izumo Grand Shrine. The Senge family have been hereditary administrators of the shrine for generations. Though legally commoners today, the heads of the family held the title of baron in the Imperial Japanese peerage ("kazoku") before its abolition in 1947. Senge Kunimaro is a second cousin (twice removed) of the present Emperor and a distant cousin twice over of Princess Noriko. He and Noriko are third cousins once removed by their shared descent from Prince Kujō Michitaka, who was the father of the Empress Teimei, Princess Noriko's great-grandmother and Senge Kunimaro's great-great-aunt. The couple are also fifth cousins through their shared descent from Marquis Nakayama Tadayasu, the maternal grandfather of the Meiji Emperor. By birth, Kunimaro is also related to other members of the imperial family. He is a sixth cousin once removed of his grandmother-in-law, Princess Mikasa, a third cousin twice removed of Princess Hitachi and a cousin of the late Princesses Takamatsu and Chichibu (a second cousin thrice removed and a fourth cousin thrice removed, respectively).