Chainsaw Man – The Movie: Reze Arc

Denji is a boy who became the Chainsaw Man with a demon's heart and he belongs to the Public Safety Devil Hunters’ Special Division 4. While floating on cloud nine after a date with the woman of his dreams called Makima, he gets caught in a sudden downpour. Taking shelter from the rain, he accidentally meets a girl called Reze. She works at a nearby cafe and smiles gently at Denji, and the two quickly grow close. From this encounter, Denji's everyday life begins to change...

Synopsis from Anime News Network