Backstory--one of the thing we authors are taught is that backstory can be a major drag. All that history between your characters? Their shady pasts? Yeah . . . don't dump it all in during the first three chapters. Spread it out, space it out, drop the readers into the middle. Right?
As a rule, this is a fabulous rule. (Duh.) But it can be tricky with characters who've known each other forever. On one of my loops we've been discussing which is more interesting, a hero and a heroine who have known each other for years, or ones who meet in the first chapter or so.
Me, I like both, but I admit there's something I adore about an H&H that already have a relationship that gets newly nudged into love. Maybe it's because I've known my hubby since we were in middle school. Maybe because it eliminates the concern of "Wow, I just had people meet, fall in love, and get engaged in the course of a few months. That's so a bad idea in the real world!"
In the contemporaries I'm shopping right now, I've got various forms of this. I've got the two who had summer fling nine years before and are tossed together again after that near-decade of silence--she's loved him all along, he's about to embark on his second marriage since then.
I've got the friends-from-the-cradle that have been in love which each other all their lives but managed to screw it up until they both came to the Lord. Then the hero more or less hunts her down in rural Missouri and determines not to leave until she gives him one last chance.
I've got the colleagues who have sat beside each other for years, but the hero never noticed the heroine until one rainy day when she finally got his attention by being her usual sweet, helpful self.
Of course, then there's the ones who actually meet--he rescues her, she chooses to trust him when she'd never trusted a man before, and I'm having a lot of fun (I say as if I've taken the time to work on this lately) developing a solid relationship that has no history at all.
So what's your favorite? The stories of sparks flying between two people who meet for the first time within the pages, or the ones where there's a rich tapestry of history behind them that you get to watch burst into flames? =)