"Takaramachi is a medium-sized industrial city that is out of touch with the development of the times and has a dense population. The sound of rumbling machines is heard all day long. Xiao Hei and Xiao Bai are the so-called "cat gang". They can soar to the top of the city and slide down in deep space. Xiao Hei will use an iron rod to crush adults he doesn't like, while Xiao Bai has... .."