How many movies have Kaori Aihara and Kohei Tsuzaki acted in together?

They have worked on 4 movies together! Their first movie together was Kyôretsu na... Aoi ana (1967) while their highest rated movie together was New Underground History of Japanese Violence: Vengeance Demon (1969). They have not worked together since Kôshoku kinchaku kiri no onna (1969).