As you can probably see on the side of your game, you have stats (Apple, Checks, Key)... Well, when you are inactive in a Casting, your Apple will go down over time. If at 0%, you will die at the next update in the game.
Yeah, castings are weird. They’re like some sort of Big Brother/Hunger Games hybrid. Not the greatest thing ever, but I think you get a lot of karma/Ts for it.