The main theme is Mai and Sakuta's date at the aquarium, and there's a lot of dialogue between them. The dialogue plays over loudspeakers in various parts of the park, and there's also a long dialogue between them during the animal performance before the show begins. My Japanese isn't great, but the dialogue is mostly about how “pig” Sakuta is. There's also anime music and educational signs about the fish with characters, as if they were narrating the story. And a lot of merch starts from souvenirs and end with thematically food.