The play tells the story of a female castle lord, Naotora Ii, who inherited the family business in the name of a man and struggled for the survival and prosperity of the Ii family all her life during the Japanese Warring States Period. Naotora Ii (Hiragana: Ii na orato, 1536? - 1582), also known as Jiro Boshi, and Buddhist name Yuenni. She was a female lord during the Japanese Warring States Period. She was the head of the Ii clan in Totomi Iidani (Inisa-cho, Hamamatsu City, Shizuoka Prefecture (formerly Inisa-gun), and was called the "female lord". She was engaged to Naochika Ii, but remained unmarried throughout her life. She was the adoptive mother of Naomasa Ii, a famous general under Tokugawa, one of the "Four Heavenly Kings of Tokugawa".