How many movies have Mie Kasai and Minami Usui collaborated on?

They have worked on 4 movies together! Their first movie together was Saint☆Young Men (2013) while their highest rated movie together was Maquia: When the Promised Flower Blooms (2018). They have not worked together since Natsume's Book of Friends: Ephemeral Bond (2018). They are most known for their animation films together.