comely young men are exploited by middle-aged panthers who boast about their conquests

Interesting -- I've only ever heard the term cougars -- oh, well, whatever - as long as it's catty?
And it seems to be a relative term. A friend told me that his 18-year-old nephew complained about all the cougars at the local hangout. When asked how old they were, he said 25 or so!