A delusional fan girl/boy who believes they can/will end up with their favourite idol or celebrity and invest an unhealthy amount of time and energy into said idol.

High levels of delulus are found in the following fandoms:
One Direction, Justin Bieber and various Kpop fandoms.

As the vast majority of them are teenage girls, their emotional maturity is almost always below zero and thusly cannot conceive the sheer thought of their idol feeling real human emotions and not actually belonging to their fans (let alone dating somebody who is not them).

Delulus often attack at the slightest hint of criticism towards their bias celebrity and are rather vicious. Note: They also have trouble separating fantasy from reality.
Commenter: It was a good performance. The last note was flat but other than that, his vocals were impressive.
Delulu: OMFG BITCH YOU DIEEEEEEE!!!!!!
by eyeofink June 19, 2014
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sometimes humorous but mostly sarcastic way of saying "Delusional" in fandoms to take a jab at opposing factions.
I can't believe fandom X thinks their ship is canon, they're so delulu LOL
by Fandomgalorz December 30, 2016
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