How many movies have Hideki Tachibana and Minoru Kunizawa collaborated on?

They have worked on 4 movies together! Their first movie together was Lewd Laboratory Unequaled Strengthening Plan (2015) while their highest rated movie together was Sex Adventure: Wonder Eros (2018). They have not worked together since Pink zone 3: Dutch wife bojô (2020). They are most known for their romance films together.