The Ryōi Shintō-ryū entry in the Bugei Ryūha Daijiten (武芸流派大事典) by Watatani Kiyoshi (綿谷 雪) and Yamada Tadashi (山田 忠史) (1963) mentions that:

"In the [‘Tōkashū’]; written in 1729 by Terada Ichiemon Masakiyo, it says that various styles were formed after Fukuno’s son and it lists the following ........Sekiguchi Yazaemon (vassal of Kii Dainagon)..."

Sekiguchi Yarokuemon (関口弥六右衛門) Ujimune, also known as Sekiguchi Jushin (関口氏心), lived between 1598-1670 and was the founder of Sekiguchi-ryū Jūjutsu (関口流 柔術).

Further context is provided by the:
Kitō-ryū Jūjutsu Kiroku (起倒流柔術記録 - Kitō-ryū Jūjutsu Record) dated 1836 and translated by Logan Weymouth, which shows the Kitō-ryū Keizu (起倒流系図 Kitō-ryū lineage diagram) as follows as above: