You finally have enough time on your hands to go to Comic-Con! You walk into a room that seems to be a voice actor panel thing. In the audience is people dressed up as all different types of characters! Mostly of Gravity Falls, hence the voice actors being the voices of Gravity Falls characters.

You decide to stand in the corner of the room and watch the panel play out. People asking questions, the voice actors answering. People making jokes, the voice actors also making jokes. And so on.