A possible son of Zachary Johnson, the second Jack-in-the-Box.
Jerome came from somewhere in the future, and traveled back in time to an evening in November 1997. This coincided with a temporal experiment conducted by two of Zachary Johnson's other potential sons from another, alternative future time rift. These two were psychotic and evil. They came to kill Zachary. Jerome, explained that time traveling can typically only be done once, just wanted to see his father alive and in person.