Switch Bitch: The Visitor, The Great Switcheroo, The Last Act, Bitch (original 1965; edition 1981)

Those four stories are:

The Visitor >> where we are introduced to the diaries left behind by Uncle Oswald to his nephew; the only treasure he could bequeath. We thus learn of Uncle Oswald's adventure in the Sinai desert after his tryst in Cairo. He meets two of the most remarkable women in his long amorous-filled life. We are also exposed to the "method" he utilizes to hypnotize women with words: "The words themselves, innocuous, superficial words, are spoken only by the mouth, whereas the real message, the improper and exciting promise, comes from all the limbs and organs of the body, and is transmitted through the eyes."

The Great Switcheroo >> Two husbands set out to accomplish something that (to their recollection) hasn't been done before: to sleep with the wife of the other without the wife knowing about it. How do they go about it you ask? Better read to find out ;)

The Last Act >> A sad story about a woman who has lost her husband and never quite let go, even with the return of an old flame from her past.

Bitch >> Returning to another entry in Uncle Oswald's diary is the story of his acquaintance with Henry Biotte, one who has devoted his life to the study of olfaction. He meets Uncle Oswald and proposes that with the financial backing of the former, he could then create a perfume which will send anybody into a sexual frenzy. "There was something diabolically splendid about a person who wished to set back the sex habits of civilized man half a million years." The question is will they succeed in inventing the world's most potent aphrodisiac?