The Tone no Iratsume's incident is allegedly a conspiracy hatched by FUJIWARA no Fuhito and his wife Agata no INUKAI no Michiyo to eliminate rivals and ensure the enthronement of Prince Obito, who was Fuhito's half brother born from a different mother.
刀子娘の事件は、異母兄弟の首皇子の競争相手を排除しようとしての藤原不比等・県犬養三千代夫婦の陰謀とされる。