When I was playing WoW there was someone in our guild for quite some time who not only ever played as girls but also told everyone he was a girl in real life for months. He had a whole "fake backstory" about his real name, relationship status, and everything. He finally let the truth bombshell drop not long before we made him get in Vent for a raid, needless to say it was rather disorienting especially because he had this tendency to "flirt" with anyone and everyone, supposedly in a bid to appear more girlish or something. I dunno. It was really weird.
Later he left and rerolled on another server, where last I heard he'd convinced the entire server that he was a girl again.