“Fan” and “fanboy” have somewhat different connotations and I’m not sure if there’s a gender-neutral equivalent for “fanboy” that’s worked its way into our popular lexicon yet.

(Example)
Fan, upon meeting George Takei: It’s an honor to meet you sir!
Fanboy, upon meeting George Takei: OHMYGOD IT’S REALLY YOU please you have to answer an argument I’ve been having with this douchebag in the TOS forum I moderate about how Sulu was promoted from being a helmsman on the Enterprise A to getting his own command of the Excelsior between the events of The Final Frontier and The Undiscovered Country, he said that that’s a totally unrealistic career arc but I disagreed and even outlined my own fanfic scenario in this screenplay I wrote do you think you could show it to Paramount for me?