The deep cultural relationship between Saiin and the Imperial Court (especially "Kokyu" - the inner palace reserved for women) can be found in "The Pillow Book" in a scene where Imperial Princess Senshi and FUJIWARA no Teishi exchange letters.
『枕草子』にも選子内親王と藤原定子の文の贈答の場面が見られるなど、宮中（とりわけ後宮）と斎院との文化交流の豊かさが伺える。