A common theme is friendship. In many fanfics, Archie and Josie are shown as good friends who support each other through various situations, like family problems or school events.
Yes, Josie and the Pussy Cats are related to Archie Comics. They are part of the Archie Comics universe and have interacted with other Archie characters in various storylines.
One great 'archie and josie fanfic' is 'Archie and Josie's Musical Adventure'. It's really engaging as it focuses on their shared love for music and how they collaborate on a school musical project. The characters are well - written and stay true to their original personalities from the Archie comics.