How many movies have Koji Eto and Yuichi Terao collaborated on?

They have worked on 13 movies together! Their first movie together was The Garden of Sinners: A Study in Murder (Part 1) (2007) while their highest rated movie together was Demon Slayer -Kimetsu no Yaiba- The Movie: Mugen Train (2020). They have not worked together since Demon Slayer: Kimetsu no Yaiba -To the Hashira Training- (2024). They are most known for their animation films together.