He was the younger brother of Sanshi TOKAI (real name Shiro SHIBA), who was famous as the author of political literature of Meiji Era, "Kajin no Kigu" (Chance Encounters with Beautiful Women).
なお柴五郎は、明治期の政治小説『佳人之奇遇』で有名な東海散士こと柴四郎の弟にあたる。