Okay, we've all fallen victim of being someone's "Stan". If you're not sure what that means, you can officially look it up in the dictionary. The word derives from (this is so weird) the Eminem song "Stan", which is about a crazed fan.
The phrase now means something slightly less intense for super fans of their favorite idols. For example I am a Harry Styles Stan. The OED now recognizes “stan” as a noun meaning “an overzealous or obsessive fan of a particular celebrity,” as well as a verb meaning to “be an overzealous or obsessive fan of a particular celebrity.” So there ya have it. Congrats Stans of the world and Eminem!