My dad loved Billy Bunter as a kid, and I guess my interest in him developed when I discovered that the Billy Bunter books on his shelf were actually worth a bit. I sort of wondered initially whether Bunter was one of those fat kids that was actually quite intelligent, but my dad pretty much said that he was completely the opposite. In fact he is a thick as a brick.
Billy Bunter is the classic anti-hero, and while this is the only book that I have read so far, it has given me a taste of what the character is like. Basically Billy Bunter is a fat, lazy, stupid, greedy boy who seems to always get into trouble, hangs around like a bad smell, and is pretty much disliked by all of his peers. Despite this he is too stupid to realise that nobody likes him, though it is interesting to note that despite his peer's dislike of him, they will actually get him out of trouble.
Billy goes to a boarding school called Greyfriars, and is always trying to get out of class, and always looking for ways to steal food to fill his voracious appetite. In fact it has become clear that even while he is in danger, his lust for food seems to always take first base. I also suspect that most of the adventures that he goes on is not because he is looking for adventure, but because he simply stumbles onto them and is simply looking for a way out.
Take this story of instance. There is a young (and quite lazy) lord that attends Greyfriars (and the only reason he is a peer at his age is because his dad died and he inherited his seat, which does not happen any more). Anyway, his father had brought a number of antiquities back from Egypt, and when a rather sinister Greek learns of it, he comes to Greyfriars to attempt to kidnap him. However Bunter, who is looking for a way to get out of detention, pretends to be the young lord, and then the lure of a luxury yacht, with food on board, encourages him to continue to play the ruse, and to also ignore his peers. This in turn lands him up in a lot of hot water, but his desire not to become a prisoner overrides the fact that he can't swim (in fact I don't think he can actually do anything).
Anyway, I would have to say that Billy Bunter is a unique character, and while we see imitations of him, and of the books, appearing here there and everywhere, I have a feeling that nobody has ever managed to create a character as painfully annoying, and as equally pathetic at Billy Bunter. In fact the American version always seems to be some sort of unshaven slob that seems to carry copious amounts of drugs around with him. From what I gather at least Billy Bunter is neat and does not smell.