Hehehehehehehehehe...
The Barbarian is actually from a rather large city. He used to be a school teacher, but after grading the same tests for several years, he ripped off his shirt and tie one day and bought a really, really big axe. He pretends to be much, much stupider than he is.
The Bard's married... three times over. His wives know he's a wandering adventurer, and have accepted it, but they don't know about each other... He may or may not have several children from these women, but he's starting to think he could take on a fourth...
The Cleric's parents died tragically in a horrible natural accident. The well-wishers came to their funeral, all uttered the same phrase... "Such a shame, taken by an act of god..." He's pledged to find this god, and kill him. The really scary part is... he's actually making headway. A cult had been operating in that area, and if not for their minor actions, the horrible accident would never have happened. Now, the cleric is devoted to wiping the world clean of this god's followers, ultimately killing the god itself.
The Druid loves nature... especially how it TASTES. He's a rampant Omnivore. He's eaten everything imaginable... but... he's still got one thing that he hasn't eaten yet... the sapient races. He's sure that they must be the most luscious, flavorful meat of them all... and adventuring looks like a fine way to learn for himself.
The Fighter has these real whangers of headaches... sometimes they get so strong that he passes out... and when he wakes up he's never in the same place he was when he fell over...
The Monk learned his technique from a folded-paper pamphlet, it cost him six copper pieces when he was a child. He still has the pamphlet, and reads it daily. though it's badly yellowed and dog-eared, the techniques described and illustrated in it are distressingly effective.
The Paladin has a girlfriend... okay, well, she doesn't know it. Y'see, He's had a crush on this one girl since they were kids and... he's never been able to express his emptions to her. Part of the reason that he became a paladin was to show off to her. Now... he hasn't seen her in several years, but he keeps thinking every day "I do this for her" and "If she could see me now..." He's more than a bit obsessive.
The Ranger keeps having these dreams... and the dreams are ALWAYS about what is going to happen. Allways. like, within a few minutes of waking up. And they never end well. Part of the reason he sleeps so poorly is because he's been disemboweled in his dreams so many times...
The Rogue is independently wealthy. Fabulously so. He doesn't have to adventure at all. He could go home and retire to his mansion right now... Except... He's an adrenaline junkie. Sure, plush beds and five-course meals are great, but hanging upside-down over a pit filled with acid while poison-coated spikes and spinning blades of doom approach from either side, and using a four-inch bit of thin metal to disable the whole contraption? that's freaking awesome!
The Sorcerer always wears a ridiculous demon mask. Not because he's horribly disfigured, but because his charisma is completely manifested through his astonishingly good looks. Whenever he removes his mask, members of the opposite gender gape in awe, and some members of the same gender. He HATES it! nobody Listens to him... they just... STARE! Dumbfounded! and they tend to follow him around doing nothing but staring at him.
The Wizard can't read magical writings. He's always had this problem. When he looks at his spellbook, (all of it cribbed from other spellbooks) he sees Lines and squiggles and shapes that don't MEAN anything, but when they all fall into place, they cast a spell. He understands that. Bug give him a scroll and ask him to tell you what it's for and... it's greek. he'll have to ID it... using some of the squiggly lines he remembers.