But to start of: Cinderella Boy is a series made out of a 1980 one-shot by Monkey Punch, author of Lupin III. And the style of the characters is very reminiscent of that. Especially the male lead, Ranma, has a very goofy side to his movements. The female lead, Rella, on the other hand doesn't bring very much to the table.
Together they're flung into an incident which alters their bodies to fuse into one and switch body functions, personalities, and so on, on a 24-hour basis.
Therein lies the biggest weakness of Cinderella Boy: two leads which share the screen time. Since the leads can't interact which each other because of the fusing, we follow two protagonists, which can't express any chemistry with each other, except for the first episode. The only exception to this is when they record videos in which they blame each other or fill the other in on details regarding their situation prior of the transformation. This routine happens in all the later episodes and gets tedious pretty fast. Luckily the anime has a good pace, but mostly struggles with its direction.
In the earlier episodes the main duo has to solve crimes/disappearances within their detective agency in a crime infested city. But the later episodes mostly ignore this setting and they have to fight a paramilitary group. While it certainly increases the stakes of the story, it was very carelessly done as the city itself offered a wide variety of story threads which could have been followed. But in the end, most actions of the side characters and enemies had extremely minor motives or simply weird points of view and explained them poorly.
Nonetheless, Cinderella Boy is an okay anime if you want an okay time-sink. It doesn't convince the viewer with the story or the characters, but with the pace it takes the viewer on a nice trip.
