Josie DeCarlo's husband, Dan DeCarlo, was the artist for the Josie comic book, as well as other Archie comics. According to News From Me:

Josie fashioned a pussycat costume for a shipboard ball on a Caribbean cruise they once took. Dan's sketches of her in that outfit figured into the later lifeā€¦and her first name provided the name of the star character when Dan shopped around for a proposed newspaper strip. When no syndicate jumped at what he offered, he offered Josie (the strip) to Richard Goldwater at the Archie company where he was already working. Goldwater accepted the idea and the comic was launched, later turning into Josie and the Pussycats, a rock group dressed much like his spouse had dressed on that cruise.

Don died in 2001, but his artwork lives on (right now, Archie is dating Valeie from Josie's band!). And it sounds like the real Josie was a pretty frisky kitty.

[The Clicker, News From Me]