According to the "Kakai-sho" by Yoshinari YOTSUTSUJI, she had been shutting herself up in the Ishiyama-dera Temple and thinking up the plan for her new novel, which had been requested by the Imperial Princess Senshi, the daughter of the Emperor Murakami.
四辻善成の『河海抄』には村上天皇の皇女選子内親王から新しい物語を所望されて石山寺にこもって構想を練っていた。