The Tales of Ise
Chikafusa likely used Kamakura period "Kokinshū" commentaries such as the extant , which speculates that one of Komachi's poems was left for Narihira after a tryst. The "Bishamondō-bon Kokinshū-chū" in turn likely worked from a then-common belief that fictional "Tales of Ise" was a genuine historical work detailing the actual events in Narihira's life (see above). Kamakura period commentaries on "The Tales of Ise" therefore tried to insert the names of real women where the original text simply said "a woman", and thus inserted Ono no Komachi into several passages of the text.