Princess Kasuga no Oiratsume (春日大娘皇女)

Princess Kasuga no Oiratsume (Kasuga no Oiratsume no Himemiko) appeared in the Kiki ("Kojiki" [A Record of Ancient Matter] and the "Nihonshoki" [Chronicles of Japan]) as a member of the Imperial family (royal family) in Japan. Princess Kasuga no Oiratsume was written as 春日大郎女 in the "Kojiki." Princess Kasuga no Oiratsume was a daughter of the Emperor Yuryaku and the Empress of Emperor Ninken. As written in the "Nihonshoki," the mother of Princess Kasuga no Oiratsume was Ominagi, a daughter of Kasuga no Omi Fukame. According to the "Nihonshoki," as wife of the Emperor Ninken, Princess Kasuga no Oiratsume gave birth to the following children: Princess Takahashi no Oitsura no Hime, Princess Asazuma no Hime, Princess Tashiraka no Hime (Tashiraka no Hime Miko; the Empress of the Emperor Keitai and the mother of the Emperor Kinmei), Princess Kusuhi no Hime, Princess Tachibana no Nakatsu Hime (also known as "Tachibana no Nakatsu Hime Miko"; the Empress of the Emperor Senka), the Emperor Buretsu, and Princess Mawaka no Hime. In "Kojiki," children of Princess Kasuga no Oiratsume were as follows: Takagi no Iratsume, Takara no Iratsume, Kusubi no Iratsume, Tachiraka no Iratsume, Ohatsuse no Wakasazaki no Mikoto, and Mawaka no Miko.

According to the "Nihonshoki," because Ominagi as a uneme (a court lady) had became pregnant with the Emperor Yuryaku after spending only one night; then the Emperor Yuryaku had doubts as to whether this daughter (Princess Kasuga no Oiratsume) was truly his child or not, and he did not raise her as her own. One day, Mononobe no Me Omuraji saw the little girl (Princess Kasuga no Oiratsume) as she walked by in a garden inside the palace; later he told the Emperor Yuryaku, that the girl bore a strong family resemblance to him. The Emperor Yuryaku replied that he had doubts whether the daughter was his own child because he thought it was unlikely that her mother had become pregnant from one night stand.
Mononobe no Me Omuraji asked to the Emperor Yuryaku, "How many times did you engage with Ominagi during the night?"
The Emperor Yuryaku answered, "Seven Times." Mononobe no Me Omuraji advised the Emperor Yuryaku that there were some women who would become pregnant more easily; then those women could become pregnant through just contact with a fundoshi (a traditional under wear for male). Thus, the Emperor Yuryaku recognized the little girl (Princess Kasuga no Oiratsume) as an Imperial princess, and the mother was elevated to his princess (consort).

However, this story was not written in the "Kojiki," and the family genealogy of the Emperor Yuryaku missed the names of the mother and the daughter. Only the daughter appeared as the Empress of the Emperor Ninken in his (the Emperor Ninken) genealogy section. Additionally, in the "Kojiki," there were only two Empresses, the Empress of Emperor Senka and Princess Tachibana no Nakatsu Hime, other than Prince Kasuga no Oiratsume, who were members of the Imperial family and do not appear in the paternal family lineage of their Emperors father's side.

However, since Princess Tashiraka no Hime, a daughter of Princess Kasuga no Oiratsume, became the Empress of the Keitai and gave birth to the Emperor Kinmei, Princess Kasuga no Oiratsume became the only existence to pass down the the Emperor Yuryaku's lineage, his father. Ironically, Princess Kasuga no Oiratsume was the only child who was to pass on the blood line of the father, the Emperor Yuryaku, to the future generations (to the modern times in Japan).