James
James is the partner of Jesse, and is her straight oposite. Even if he's supposed to be evil he is quite nice to others and easy to tears, and he is more easy-going than his teammates, and the lesser evil one.
A good example on this is that when both Jesse and Meowth left their teammates for the greater good, he did the opposite... well, he could marry a beautiful young lady obsessed with making him a gentleman and get filthy rich, but he decided against it (gee, wonder why) and stayed with his frieds.
He also seems to be more willing to team up with Ash and his friends when needed than his compadres. James is actually what one could describe as plain out wussy at times, and he certainly doesn't seem to have anything against it... he is the only member of the team known to do decent cooking, and the ammount of time he is in dresses is quite impressing as well. But I'm not going into his gender preferences here, so read about it here if you're interested.
James does have a pretty interesting past as well. He is the inherit to a large mansion and family fortune... if he marries Jessiebelle, a southern lady who looks more or less similar to his partner and likes to chase people around with whips. His parents engaged him to her at a young age, and James ran away from his home when he at least couldn't stand any more of her attempts on making him a proper gentleman. (And, according to himself, later died in the snow as Growly, his Growlithe, howled in sorrow over him.)
He also had a grandfather, and was picked on in school because the older kids were jealous over his clothes, which all were in fine Mareep wool. And, unlike Jesse, he ate ice cream sandwitches and swam in the "Olympic pool" (?) in their garden during Children's day.
What happened after he ran away from home isn't known, but at some point he was in Pokèmon Tech (an expensive school), and when there he did know Jesse. Later on they joined a bike gang together, and.. well... after that they joined Team Rocket.
It's nothing more to know about James's past (heck, it's way more than we know about anybody else in the show!), except he took classes in modern dance.
As so many else on the show, James dreams about becomming a pokèmon master, and... well... that's it. I think.
but that dream probably won't get fulfilled in quite some time, if ever... the he has two pokèmon, a sucky Weezing and a Victreebell that keeps trying to eat him.