Presenting

...A similar custom is the buttocks-smacking festival at Iwakura Shrine in Kyoto. Also, animals have a behavior called "presenting," which is related to submission and sex, but for humans, the meaning of turning one's buttocks toward another is different. Tsukinokishi Ikina, who was captured by Silla, stuck out his buttocks toward Japan and was forced to say, "General of Japan, bite my buttocks," but he refused and continued to cry out, "King of Silla, bite my buttocks," and was killed (Nihon Shoki).

*Some terminology explanations that mention "presenting" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…類似の習俗として京都の石座（いわくら）神社には尻叩き祭がある。また，動物には服従や性と関連したプレゼンティングpresentingという行動があるが，人では尻を相手に向けることの意味は異なる。新羅に捕らえられた調吉士伊企儺（つきのきしいきな）は，日本に向けて尻を出し〈日本（やまと）の将（いくさのきみ），我が臗（しり）を嚙（くら）へ〉と言えと強いられても屈せず，〈新羅の王（こきし），我が臗を（くら）へ〉と叫び続けて殺されたという(《日本書紀》)。…

※「presenting」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報