JESSE
Jesse is the other member of Team Rocket. She bosses James around (which I think is cruel) and assumes control over the other two members.
She has a short temper which can be quite harmful to anyone's health, and a attitude unmatched to anyone else.
Her past is very vage, but some information is out there. Her mother was a member of Team Rocket, before Giovanni assumed control and his mother was in the chair, and was sadly killed in a mission by an avalanche.
Jesse may in fact act the way she does because of her tragic past. She does have a soft side for James, but no one knows if it's friendship or something more...

JAMES' POKEMON
Koffing was James' Pokemon that he used in Team Rocket. Although not very bright, it was loyal to him and never disobeyed him, and even had the heart to evolve for him into Weezing.(How's about that, Ash?)
Weezing now happliy serves James in and out of battle. He can go up against a Pokemon, or great for getting away by using Smokescreen.
Victreebel, by all means, got to him mysteriously. He picked it up in "The Breeding Center Secret" saying that it was his. It attempts to eat him, but all and all it still obeys him.
Magikarp was definitely a Pokemon not to be forgotten. He bought it on "Battle Aboard The St.Anne" from a vendor. He thought the fish could promise him a fortune. Instead, all it brought was pain. Evolving to Gyarados didn't make things any better.
Growlithe was a childhood pet. "Growlie" spent his life playing with James, until Jessebel came along. He was locked up in a doghouse until "Holy Matromony", when he was freed just in time to save James from his evil fioncee.