How can people write a character that hasn't appeared on the show yet?????
I may write UC - and in the case of Heroes, AU – pairings, but I remain a stickler for all other canon details. If we've never actually seen the character, aside maybe from promo photos/spoilers, how can an author accurately write them?
Also, I'm doing my damn hardest to avoid spoilers and don't appreciate being subjected to characters that are new popping up in fic.