Misc. OC's are characters that aren't intrinsically involved in a story line/time period. These are general characters that I enjoy drawing.
Island Friends are characters that live on Jackson's tropical island. They can be depicted with Misc. OC's but should not be drawn with characters from 60's or Streets of London.
'60's characters are characters that are involved in Novacaine's plot. They canonically live in the 1960's and should not be seen with modern day characters or characters from Streets of London.