How many movies have Koharu Yamasaki and Naohiro Hirakawa acted in together?

They have worked on 1 movie together! Their first movie together was Yumeno Maria: Chô-inran onna no shiseikatsu (2002) and was their highest rated movie together. They have not worked together since Yumeno Maria: Chô-inran onna no shiseikatsu (2002).