Why you should watch this: The main character doesn't actually visibly move. He just sort of...teleports from scene to scene. If you're the type who likes to have a firm logical grip on reality this is really not for you. A lot of things don't exactly make sense, but overall it's really not supposed to, and in fact I think it kind of makes fun of itself in a way.
Very episode-to-episode style, but the relationships between the characters do develop in a satisfying way. This would be a good animé as a sort of intro for kids. It's definitely lighthearted in general, though it's still got some points serious enough to make it not totally silly by any means.
If you've got a bit of a silly sense of humour or you like something vaguely, but not totally mindless, I think this animé is worth watching. Uber-serious watchers are best advised not to approach.