1. Someone suffering from a belief that there favorite character is a super cool badass based of them just liking the character. The character in question can have no feats near what a person suffering from DFS says he can do.
Ex: A person suffering from DFS would think Krillin is the strongest fighter in DBZ and would be strong enough to fight Perfect Cell and win with no help.

2. Someone suffering from a belief of their favorite characters needing extra care/exposure when they serve no real purpose to the overall story arc of the series they are in. They make up random scenarios to put their characters in, but unlike fan fiction writers it is their own headcanon that they try to spread to everyone.
"Stephanie Brown would mop the floor with Batman in his prime"
"Robert, you are suffering from Delusionary Fanboy Syndrome"
by Mr_JayJay24 April 28, 2020
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