Who is John Bickerson Bolling aka Jack aka Binx from The Moviegoer and what is their importance?

John is the main character in the novel. He has a number of nicknames, although as a character, he does not seem affable enough to deserve the nicknames. Instead, the nicknames seem to be more like representations of the type of person the other characters wish he was. For example, his clients and Sharon will both call him Jack as the relaxed, yet educated financial investor. On the other hand, his friends and college mates refer to him as Binx which is a much more playful name. Hardly anyone calls him by his real name, John.