Yorinari was a son of Masafusa and took over the Toki following the death of his elder brother Yorizumi in 1548. He resided at Inabayama. The authority of the Toki, already tenuous, steadily eroded under Yorinari, due in no small measure to machinations of Saitô Dôsan. Yorinari was finally overthrown by Dôsan in 1542 and went off into retirement, at length wandering from province to province. Following the death of Oda Nobunaga at the Honnoji in 1582, a number of Yoriaki's old retainers invited him to return to Mino, though he died soon afterwards. He may have been the biological father of Saitô Yoshitatsu: around 1526 Yorinari gave Saitô Dôsan his favorite concubine, although the circumstances surrounding this event are hazy. Less than eight months later, this concubine gave birth to Yoshitatsu and so, naturally, his parentage was questionable.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005