A weirdo who allways insists on showing off HIS new toys. He is really a child inside, who flirts with his best friends constantly like a perv.
An allchin is allways a nobhead.
An example of this would be him showing of a new car or a new gadget such as a new ipod which he can only afford of his grandmas catalogue. An allchin thinks he is sooo posh because he works in a high profile company such as Yorkshire Bank or Barclays Bank. But every one knows he often started of in a place like McDonalds or a pound shop.