The Court-Entering Sparrow is often cited as a case where personal grudge takes the form of a small bird that slips in and out of the imperial palace. Its pecking at offerings in the Seiryōden symbolizes trespass into forbidden precincts and the ill omen of defiling sacred food, feared for disrupting court ritual. It was taken as the metamorphosis of Fujiwara no Sanekata’s exile to Mutsu and his unresolved yearning for the capital, and used to explain calamities and blights. A revelatory dream at the Kangakuin and the raising of a Sparrow Mound reflect medieval rites of pacifying vengeful spirits through Buddhist memorials. Real sparrows’ migrations, flocking, and seasonal crop damage underlie the tale, which fused with the idea of visiting birds as vessels for souls. The tradition appears across various records, but details and dates differ, leaving much uncertain.