I'm just compiling a list of ideas for people to take a gander at when they want to plot. AUs/Dark!Character flips and the like. Will add more as I think of them.
War: Your character and mine have been assigned to the same unit in a war. They are also battle buddies.
Lost: Your character took a wrong turn at Albuquerque - my character is going to try to guide yours home
Shipwrecked: We were on a three hour cruise, now we're the only survivors.
Zombie Apocalypse: That's it, they're done for. Might as well go down swinging right? Or maybe they can beat this thing....somehow
Medieval Court: Avoid court scandal? Is your character a prince and mine a princess from a far off court, are they courtier friends? Sky's the limit.
Revenge: Your character has called on mine to exact revenge on someone for something (npc or third character, or fourth welcome)
Absolution: Something terrible happened, and our characters were the cause. Guilt eats away at them every day. Do they find a way to make things right? Or spiral into darkness?
Broken Home: They were happy once, and then they weren't. Our characters are in an abusive relationship.
Take it and leave: Our characters are part of a hold up, are they victims or perpetrators? Worse yet - are they on opposite sides of this equation (best suited for 3+)
The Asylum: One of our characters has been deemed "mad", and the other is the assigned Physician to cure them of this madness.
Stepford: A hoity toity gated community has extended an invitation for our big wig characters to move in. What happens when the wife becomes...perfect?
Saying Goodbye: One of our characters is dying, and instead of just telling the other, they take them on a whirl wind travel tour - ticking off things on their bucket list with their best friend.
You Owe Me: Mafia families with two kids who are best friends. Merger in the making, or war?
Shackled: My character finally got caught, and the only way to save them is to have them shackled to yours for a month.
Star Struck: Our characters space craft has broken down, and life support is on the fritz. Can our character's fix the problem or will they die in space?
Glitz and Glam: Personal assistant to the rising Star. Are they friends? or do they hate each? Are they lovers?
The Crash: 30's Depression Au
I'm Sorry: My character feels guilty for being behind the wheel during the accident that left yours in the hospital.
Drunken Mistakes: Did they get married? What's going on? Our characters can't remember and have to piece together the night before.
Dark Siders: Flip character alignments