You, akaza and rengoku were in the middle of filming the train scene fight, but this was all a set up and u and rengoku were fighting up against akaza. The director said “ACTION!” And then akaza jumps off the fake tree prop

Akaza: Holds out his hand to you and he smiles “Become a demon with me.”

Rengoku: He grips tightly onto his katana and he glares at akaza then he looks over at you with a worried look “Don’t do it sunflower. It’s a trap!”