Killing Spree 4
After Jase stole a tank he met Jimmy on the roadside and invited him to join him in blowing up the school. Jimmy accepted. They switched to a green Camero when the tanks grenades stopped working. However, they already damaged the school and the Janitor called the police.
Killing Spree 4A
Jimmy drived while Barry and his wife Julie pursued them, Jase stopped the cops by jumping onto the hood of the cop car flipping it over.
Killing Spree 4B
Jase told Jimmy about his experience with Glenda while they approached the city.
Killing Spree 5
Jimmy drove off when the SWAT team and a still alive Barry (even though his wife died in the crash) arrived. Jase started his rampage and Barry went after Jimmy after his helicopter was destroyed. During the prisuit Jimmy ran head on into Barry's motorcycle but ultimately just gave Barry a way into the vehichal. Jimmy was knocked out and the car crashed inot a shop window.
Killing Spree 6
Jimmy and Barry survived and Barry shot Jimmy in front of Jase.
Killing Spree 7
In Killing Spree 7 Jimmy's corpse is still seen, and he appears alive in a flashback where Jase stopped two teens from beating Jimmy up. This memory gave Jase the strength to ressurect himself (As the Killer).
This may be the way that Jimmy and Jase met.
In all three of his speaking appearances in the series, Jimmy has been voiced by a different actor each time. John Carberry provided the voice of Jimmy in Killing Spree 4. In Killing Spree 5, Bryce Nussaumer voiced Jimmy. For his last appearance, Jimmy was voiced by animator Aran Saunders.