Showmance

Stiles is an up-and-coming actor, and has somehow managed to become loved by both the media and the fans, even though he's just the main character's best friend on the TV show he's starring in. When Finstock, the writer and executive producer of the show, messes up, Stiles is forced to pretend to be dating someone to save both the show and his job. Said someone happens to be Derek Hale, an actor who has been in the industry for a long time, but is now risking his new show where he has the main role, because of his bad behaviour towards media and the fans. So it's a win-win, really. Or: the one where Stiles and Derek are both actors who needs to pretend to be in a relationship to save their asses, and lie to everyone around them.