A Fiddlesticks Main is a person who mains the champion Fiddlesticks in League of Legends.
Most of them have severe trust issues due to the sheer amount of false skin leaks and false promises from Riot Games.
It's worth noting that they usually don't play any other champion in the game.
Person 1: Oh, so you are a Fiddlesticks Main?
Person 2: Yes.
Person 1: Have you seen the newLeonaskin?
Person 2: mentally breaks down
The name given to an individual so completely devoid of linear thought, initiative, or attention span that any attempt at communication with them leaves you as sharp as the leading end of an orange. See also: Crackhead
Ol Fucky Fiddlesticks held me soft hostage for nearly an hour rambling on about how he's been planning on converting his mother's answering machine into a drone so he can run counter-surveillance on the "I'm fucking serious dude, a robot bird" he suspects got his cousin busted for manufacturing last year. Dick.