How many movies have Hiroyoshi Koiwai and Yu Aoi collaborated on?

They have worked on 5 movies together! Their first movie together was Shining Boy and Little Randy (2005) while their highest rated movie together was Rurouni Kenshin: The Final (2021). They have not worked together since Rurouni Kenshin: The Final (2021). They are most known for their adventure films together.