And one character always turns out to be gay. Similar situations arose during my time on The Real World, both in game and out of character. Only the minority cast members came to the show with a character concept. The white kids would create theirs as the season progressed, randomly changing their alignments much like Amaya's Athasian half-giant. If you have a Real World party, you can run a Road Rules adventure.
Adventures are mission based and unconcerned with the abilities of the party members.
Each adventure will challenge the characters to do things they probably can't do. A party of 3 owl bears and a mute half-elf might be sent to win a karaoke contest. Missions are completely unconnected, so failing one won't set the party up for an even bigger failure next time. And when a party member gets voted out of the house, or a cast member inexplicably kills the next innocent bystander they come across, it doesn't destroy the story, because there wasn't much to begin with. Real World parties, lacking character consistency, will spoil a carefully constructed campaign.