How many movies have Aya Hirano and Koichi Yamadera acted in together?

They have worked on 6 movies together! Their first movie together was The River's Light (2009) while their highest rated movie together was Gintama: The Very Final (2021). They have not worked together since Go! Anpanman: Dororin and the Transformation Carnival (2022). They are most known for their animation films together.