This is a "sleaze" paperback, a style of book that focused on novels centering around people engaging in abnormal sexual relationships. The actual content of the books tended to be suggestive but not explicit or obscene, with a tendency toward melodrama. Many of these formed the first exposure of things like lesbianism & homosexuality, open marriages, swapping, domination/submission, fetishism and nymphomania/sex addiction to the general public. Some of the cover artists are justifiably famous.
From the publisher:
The Naked Canvas - Every man coveted this beautiful model with the perfect body.
French Maid - A girl from Paris who brought her French ways into a house of secret passions.
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