Tamayori-hime is the daughter of the sea-dragon god Watatsumi and the younger sister of Toyotama-hime.
[1] The word tamayori-hime is a generic term for shamanesses who dedicated their lives exclusively to their deities.
The Japanese folklorist Kunio Yanagita espoused the view that tamayori-hime means "a consecrated women to whom a spirit descends" and that the intimate relationships between the two helped generate belief in mother-son pair deities.
[4] Miyaura Shrine (Miyazaki Prefecture Nichinan City) is said to be the site of Tamayorihime's residence.
However, if we compare the generations of those who accompanied the descendants of the gods [ja] with those involved in the Jimmu East Expedition, we find that the Nakatomi-ren, Imbibe shu, Kume nao, and other related clans are always grandfather and grandson, and only the imperial lineage is somehow one generation older.
This has led some to believe that the genealogy of Ukusa-thatching-furinushi-no-mikoto and Emperor Jimmu is a corruption of the tradition of sister marriages common among horsemen, and that Toyotamabihime and Tamayoribihime were sisters who married Hoori, with the former giving birth to Ugayafukiaezu and the latter to Emperor Jimmu and his siblings.
According to this theory, Ukusabufurinushi-no-mikoto and Emperor Jimmu were both sons of Hiotorinushi-no-mikoto, making them half-brothers, and the number of generations is consistent with those of other related authors.