Subaru Hasegawa is a high school freshman, he joins the basketball team but soon finds out the team is inactive because the captain is being suspected as a lolicon. He miraculously is entangled with the job of being the coach of an elementary schools basketball team. With these girls and their love for basketball Subaru will have a hard time getting acknowledged by each of them.
I have a high tolerance for moe shows, lolicon shows and elements. Sadly, even these elements could not save this show from being just run of the mill. Nothing rises above mediocre and is mostly forgettable. The music is generic, the character designs are generic and even the voice acting is generic. There is some fanservice and unless you either have a high tolerance for loli fanservice or you gobble this kind of fanservice it is going to turn some potential fans away. The only redeeming quality if you can even call it that is the cast is likeable.
Ro-Kyu-Bu! is other than a moeblob loli show, completely forgettable and almost unwatchable. I guess if you like lolicon and moeblobs you could check it out, but if you want something with a bit more substance look elsewhere.