Jimmy Stone
Jimmy Stone was a boy for whom Rose Tyler left school prior to sitting her A levels. At the time of the 2005 Auton invasion of London he had apparently not attained much success. As Rose said to the Auton version of Mickey Smith, "look where he ended up." (DW: Rose)
Behind the scenes
A non-narrative article in the Doctor Who Annual 2006 gave further insight into Stone's character. According to this source, he was a twenty year old musician. After falling for Jimmy, Rose dumped Mickey, left school, moved out of home and lived with him in a bedsit. Their relationship ended in tears five months later and Rose was left £800 in debt, while Jimmy was in a camper van to Amsterdam with a woman called Noosh. He later ended up in prison and then started to work as a door-to-door salesman.
However, this same article includes obvious contradictions with the television series about Rose's age, so its accuracy is dubious. Furthermore, none of its information has ever surfaced in an actual story in any medium.