Small piece of trivia

I just rewatched the beginning of this movie yesterday (trying to practice my Japanese) and I noticed something I didn't realize the first time. When K and Hinano "meet" for the first on the train, he's singing "inu no omawarisan", a popular children's song in Japan, and basically is about a lost kitten and how she can't remember her name or where she is from, so the dog policeman is troubled and worried about her. The thing is, the english subtitles I watched the first time translated this very strangely: "The dirty cop is looking for trouble" or something like that. It was quite confusing to me at that time and I basically assumed K knew her brother was after him and upset about it. When I realized the truth, it became much more delightful and subtle :)