How many movies have Koji Okumura and Masahiro Kasai collaborated on?

They have worked on 8 movies together! Their first movie together was Pink Physical Examination (1985) while their highest rated movie together was Za gyakutai: Nyotai ikedori-hen (1987). They have not worked together since Subway Serial Rape: Lover Hunting (1988). They are most known for their drama films together.