Common species which exist on every forum
They are supporters of particular verse/character. They always let their opinion to guide their arguments, that's why they're always biased. They think vs threads are popularity contests. Their arguments are full of fallacies, that's why they can't win against anyone who can debate properly. Some of them aren't that bad and can concede when they realise they're wrong but some people like infamous Phenom Brigade would never admit defeat, no matter how many times their arguments have been ripped to shreds.
Fangirls is a female counterpart of fanboys. They are obsessed with characters which are Made of Fail (Uchihas, Cullens) and sometimes can be even more difficult to deal with than fanboys.
It should be noted that MF Arena was crowded with them at first but nowadays their numbers decreased drastically because more and more quality debaters join the forum
Examples of their "logic":