Immoral Wife (2005)
A wife thinks that all her sexual perversions and promiscuity is all behind her when she got married. But a friend of her husband who comes over for a drink will prove her wrong.
Wife/Girlfriend Sharing
Candido Erotico (1978)
A guy is hired by a couple to screw the wife while the husband watches and to also have a threesome with them. He falls in love with their daughter and marries her, to the couple’s chagrin. He can’t perform in bed with the daughter without an audience, so his mother-in-law suggests something.