It's quirky, stupid, and annoying. Yet, at the same time, it can be very enjoyable.
Now, to start out, the story (yep, there is one) is, amazingly, cornier than Klonoa: Dream Champ Tournament. Basically, different characters have all been invited to participate in a Volleyball tournament, all of them coming from different areas of the Klonoa Universe (many wouldn't have met otherwise). You've got good ol' Klonoa (obviously). Lolo, Popka, Tat, and Leorina from Klonoa 2. Joka and Natatomb (who looks uglier than before) from Klonoa 1. Chipple from Empire of Dreams. Guntz and Garlen from Dream Champ Tournament. And, finally, a Moo (one of them little red enemy things). Four of them will have to be unlocked by playing though the championship mode.
Now for the actual volleyball portion. The gameplay is very hard to learn (maybe that's because I've never played a volleyball game), but once you do get it down, it becomes quite easy. Although, the AI isn't that way. The AI in the game are tough, albeit not very smart. They can deal pain to you and your teammate, but there are times when the AI could have hit the ball, but end up missing or getting knocked right out of the court. This gets very annoying if you have a computer player for a teammate, because there are moments when you want press a button and have your character strangle your teammate. (Sadly, that wasn't implemented) At least there is an option where you can control both members of your team, which is also hard to get used to but works much better than having an AI as a teammate.
Have you ever wondered what the Klonoa characters sound like speaking in English? Well now you can in KBV, although NAMCO picked some very bad actors. Almost everything any character says is corny and annoying, and to top it off, is spoken in thick British accents. Annoying? You bet. Enough to stick Duct Tape on your TV's Mute button? Thankfully not. Besides, if you get annoyed of the English voices, there is the option to change it to German (or Spanish, French, etc.) Replay value isn't very present in the game, unless you enjoy the exhibition mode. All of the characters and levels can be easily unlocked within an hour of playing the game, so don't expect any great length to the game. The graphics are also something that could have been worked on, especially for a late generation PSX game.
However, even with all of these things, KBV can be a very enjoyable game, and provide some fun for Klonoa fans. It is quirky, stupid, and annoying, but it isn't totally bad either.