I usually can only see this in a gta type world though if you have another idea let me know.

These people are opposite of normal people in both personality and color scheme.

Also, some have new names.

Evan = Vanti
Delirious = Delirium
Wildcat = Zipcat (He's fucking adorable.)
Nogla = Night
Moo = Moon
Terrorizer = Broken
That's it as far as I know. Tend to call 2p Basically Nasically/Nasic

Scenarios!

1. You fall into this new world from either finding a portal or it appearing because of something or someone(Brian!)

2. Same as normal gta scenario one

3. Make up crap.