Unusual ring found in antique shop...?

I found this bizarre ring in an antique shop the other day and was curious if anyone might know if there is a traceable origin. The ring is sterling silver, with no inscriptions, and on top is a molded scene of a man and woman making love, with the man taking the woman from behind. I purchased the ring but there was another piece that looked as though it may have been made by the same artist. This one was of a naked woman, spread leg and riding the crescent face of the man in the moon. I know this all might sound like a joke, but it's really not. I'm just curious who would make something like this and for what purpose (as in who would really wear it?). Any information would be great.