Let's see~
Pewdiepie users, characters and even the occasional person who claims to know 'im.
People who claim to know celebrities in general.
The 'OMFG HES SO HOT!!!1' people.
There ARE, in fairness, some good fangirls out there that can carry intelligent conversation about their obsession, and not creep everybody out. These are the best, as good discussions can grow from this...
BUT THEN there are the ones that cross the line, set fire to it, and keep running.