A jagbag could be a friend dependent upon what context it's used in. It could also be used as an insult.
Word was derived from the combination of jagons featured in South Park. The episode was with
earth as a reality TV show. The other portion of this word comes from a
beer called Jaguar
Ice with a black jaguar with florescent green eyes.
What's up ya jagbag, how ya been?
That jagbag slashed my tires.
What
the fuck is that jagbag doin' with my woman? I'm gonna
slash his fuckin' tires, that cock
sucker.