How many movies have Hidenori Arai and Mayumi Tanaka collaborated on?

They have worked on 3 movies together! Their first movie together was Dragon Ball: Sleeping Princess in Devil's Castle (1987) while their highest rated movie together was One Piece: Baron Omatsuri and the Secret Island (2005). They have not worked together since One Piece: Baron Omatsuri and the Secret Island (2005). They are most known for their animation films together.