Give the Lady a Hand, The Big Easy
In mainstream films, sex between two characters who are attracted to each other is almost always easy, once it occurs: everything gets hot and steamy and it's instant orgasms for all. The Big Easy (1987) is an exception.
New Orleans distric attorney Anne Osborn (Ellen Barkin) is falling in love with bad-boy cop Remy McSwain (Dennis Quaid), but when they go to bed together, the usual hot-and-steamy doesn't happen for her. She stops and says she's no good at sex, but he reaches down with his hand and changes her mind.
This scene still stands out among the millions of scenes of women instantly melting underneath men.
Come to think of it, the film is like that great New Orleans movie, Streetcar Named Desire, if that movie were a film-noir crime story with a happy romance between the two main characters instead of what it is, which is quite the opposite. So I guess it's not like it at all, except that Streetcar also does not show the heroine melting into the strong man's arms: Stanley (Marlon Brando) quite clearly rapes Blanche (Vivien Leigh), and she does not enjoy it.
[The image is from the Big Easy's movie soundtrack, which features Cajun, zydeco, and other Louisiana styles.]