Jessie is 17, according to 'The Ultimate Test' but is really 21 years old according to the CD drama. We will round and say she is 19. Her hair is kinda a dark magenta/red-ish color and her eyes are blue.
Not a lot is known about Jessie's past. She was born into a poor family and her mother, Miyamoto was a member of Team Rocket. Miyamoto was sent on a dangerous mission to catch Mew and died in an avalanche, supposedly. Nothing is really known about her father. Jessie was sent to a foster home after that. When she was little (before her mother died), she loved to eat snowgasboard. It was something her mom made from snow and soy sauce and remains one of Jessie's favorite childhood memories.
One Christmas, a Jynx dressed as Santa, came into her room and stole her doll. This resulted in Jessie thinking that Santa was a thief. Although this mix-up was cleared in 'Holiday Hi-Jynx' it totally ruined the little girl's belief in Santa.
A holiday that Jessie actually enjoyed was Princess Day but she never had her own dolls.
At school, Jessie was the only kid who didn't have a balloon case for her pencils because: 1. she was poor, and 2. she only had one pencil to begin with.
Sometime after, she went to Nurse school for Chanseys. She befriended one and was reunited with her much later. Unfortunately, they couldn't really stay together because the Chansey would lose its job as a Pokemon Nurse Joy helper. Something like that. But she has half of the Chansey's egg necklace.
Jessie first met James at Pokémon Tech and they became very good friends. The night before the big exam, they 'frolicked all night, for their future seemed bright!' but they got the lowest scores in the history of the school.
Jessie joined the Bridge Bike Gang where she was known as Big Jess/Chainer Jess because she rode around swinging a chain above her head.
Of course, after, she and James joined Team Rocket, became partners and met Meowth.
Apparently, sometime during the Team Rocket, she had a (sort of) friend named Wendy. Jessie had a fruit smoothie and left this Wendy with the bill. And for some reason, this Wendy was still stuck on this.
Some people say that Miyamoto didn't die and is now Lorelei of the Elite Four. But of course we meet "Lorelei" later and apparently her name is Prima now. Right.
Jessie is sometimes seen as very vain, kind of overbearing woman, but that's her character and why some of us have grown to like her. She is constantly trying to look her best (don't we all?) Jessie has a very short temper and uses her "weapons" on anyone who messes up her face or angers her. This wass towards the beginning of the series. Jessie hardly uses her weapons in the Johto. There are fond memories of the fan and the frying pan. Lord knows where she kept it all.
Jessie has an Ekans she recieved for her birthday which later evolved into Arbok. But then Arbok and Weezing left to take care of the Koffings and Ekans that were being poached. She used to have a Lickitung but it got switched accidentally with a Wobuffet. She currently has a Dustox (evolved from a Cascoon which evolved from a Wurmple) and a Seviper.
Also, there's a memory that Jessie's pretty fond of about Little Root Town, but we have no idea what it is. Jessie also has pretty good eyesight; 20/20, apparently.
