Whenever a fan is so "loyal" to something that they fail to see what's wrong with it. With a series, this may be the denial of any plotholes, bad creative choices, repetitiveness, or just plain stupidness. Fanboy blindess isn't restricted only to series, it can be used towards actors, companies, and many more things or people. The most prominent case of fanboy blindess in today's society is amongst fans of the Call of Duty and Twilight franchise. Someone suffering from fanboy blindess is generally in love with what they are defending, and refuse to accept any statements against it, and accept every or almost every creative decision made by the creator with gusto. They are very forgiving and accepting towards the company or creator, and are nearly impossible to reason with until either the defender becomes open minded, or until the defended finally makes a mistake so questionable it leaves even the fanboy(s) puzzled.
Fanboy: "Dude, are you going to get the new Call of Duty?"
Person: "Nah, the previous one was alright, but this one looks way too much like it, there's nothing new."
Fanboy: "ARE YOU DUMB?!? IT'S SO DIFFERENT NOW! THEY HAVE NEW GUNS AND MAPS, AND YOU CAN LEVEL UP YOUR WEAPONS NOW!"
Person: "Don't they release new maps and guns like every week? Leveling up weapons in an fps is just stupid..."
Fanboy: "WHATEVER MAN, DON'T BE A HATER JUST BECAUSE YOU HAVE SHIT TASTE IN GAMES!"

Fanboy: "OMG I love Twilight! The new movie is amazing! Cinematic masterpiece!"
Person: "What? You're kidding right? How can you not tell how terribly generic and scripted the writing is? Even the acting is atrocious."
Fanboy: "You're just too dumb to see Twilight for what it is! Team Edward FTW"

A case of Fanboy blindness towards a company.
Person: "You know, Dead Space 3 would be a lot better if I didn't have to pay out of my wallet in order to upgrade my gun."
Fanboy: "You don't need the upgrades, and besides, it barely costs anything, cheapass.
Person: "But it could have been included on disk, there were like 11 day one dlc..."
by black white man April 15, 2013
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