panboy

A person who is single-mindedly convinced that a certain product from a certain company (usu. video games) is poor quality. This person is usually so closed-minded that the only way to really get the point across is to make fun of the word fanboy. Derived from the words fanboy and "pan", which aside from its more common definition means to harshly criticize. Initially invented for the purpose of protecting Nintendo and anime fans from being called fanboys when they really aren't, though it is not just for their use and can definitely be used against them, if done properly.