This leans a bit towards the milder side but I would be curious to see if someone took this up as a multipart story and do a better job with it than I could.
Husband wants to introduce his wife (and himself) to a BBC dominated Hot Wife - fem cuckold situation but is unsure of her response. They know a black couple whom the husband learns are experienced in this. He arranges to rent a beach property they own for two weeks. Shortly after arrival, the couple discover their hosts' collection of toys, wardrobe, interracial videos, books, magazines. etc. Before long they are trying out the toys first with the bbc dildos on her - then on him. Then the plug for him. And by the end of the first week she's using the strap on. By beginning of the second week, they've begun husband's feminization, including a cage they found (which mysteriously fits). By the end of the second week, she's pegging her fully feminized, baby doll and makeup wearing husband when the Black couple surprise them and join in beginning their education in their new and welcome life.
Husband wants to introduce his wife (and himself) to a BBC dominated Hot Wife - fem cuckold situation but is unsure of her response. They know a black couple whom the husband learns are experienced in this. He arranges to rent a beach property they own for two weeks. Shortly after arrival, the couple discover their hosts' collection of toys, wardrobe, interracial videos, books, magazines. etc. Before long they are trying out the toys first with the bbc dildos on her - then on him. Then the plug for him. And by the end of the first week she's using the strap on. By beginning of the second week, they've begun husband's feminization, including a cage they found (which mysteriously fits). By the end of the second week, she's pegging her fully feminized, baby doll and makeup wearing husband when the Black couple surprise them and join in beginning their education in their new and welcome life.