Fire Emblem: Nephenee/Heather (eitgher gen together or femslash), post-canon adventure fic. This could be Heather not giving up her fabulous career as a thief despite what the credits roll says, Nephenee defending the town with a militia again, or any other kind of adventure that strikes your fancy (and if you've got a way to work your other likes, such as science or time travel, into the plot then I am absolutely game for that). Any other characters you want to include would be fine, as well.
Fire Emblem