How many movies have Shōji Sakai and Yutaka Arai collaborated on?

They have worked on 2 movies together! Their first movie together was Chô inran Aida Ruka: Kuwaetara hanasanai (1997) and was their highest rated movie together. They have not worked together since Sekuhara shûshoku mensetsu: Joshidai nama naburi (1997).