I just want MCR GSF in which the reason they look so messy and shaggy at m&g's is because they've just finished having awesome sex. I suspect this is impossible, because m&g's happen right after concerts, right? But I still want it

Oh man, yes! And it could happen because the festival M&Gs seem to be happening before the shows, and surely some group sex is just what you need to get in the mood to perform.