I start my characters off with a word or two as their core and build from there. They tend to become products of their environment over time, though...
Keiichi: Camaraderie and Amusement
Araia: Serenity
Azrea: Like-a-puppy-with-floppy-ears (seriously)
Seri: Distracted (even before she went off the deep end)
Min: Dignity and Pride
Kin: Confidence and Zest
My first character, Baiko, was orginally inspired by Tomoe Gozen, but she didn't end up anything like her :p