Princess Muneko (統子内親王; 13 August 1126 – 20 July 1189), later known as Jōsaimon-in (上西門院), was a princess and an Empress of Japan. She was the daughter of Emperor Toba and Fujiwara no Tamako.She served as Saiin at Kamo Shrine in 1127-1132. She retired from her service as priestess for health reasons. She served as honorary interim Empress of her nephew Emperor Nijō awaiting the appointment of a permanent Empress. She retired when her nephew married his aunt, her half sister Princess Yoshiko (Nijō). In 1160, following her mother's example, she took ordination as a Buddhist nun at Hōkongō-in.