How many movies have Ryo Takahashi and Seiichi Shirato collaborated on?

They have worked on 4 movies together! Their first movie together was Princess Principal Crown Handler: Chapter 1 (2021) while their highest rated movie together was Princess Principal Crown Handler: Chapter 3 (2023). They have not worked together since Princess Principal Crown Handler: Chapter 3 (2023). They are most known for their drama films together.