Modern-wise I'd recommend Graham Travis' Portrait of a Call Girl, it is impressionistic plotwise but has some scorching sex between Jessie Andrews and Manuel Ferrara and Liza Del Sierra looks delicious in a lesbian scene.

For the 'classic' era (70s/80s) there are loads of great movies, the best mix of plot and sex is without doubt Amber at Night, a major classic that demands the Melusine treatment.

A lot of other 70s films are much darker in their portrait of sex work, They Called Her Lisa is so nightmarish it's almost anti-erotic but the same director's Midnight Heat, although brooding and noirish, is more conventionally hot if heavy with monologues by Jamie Gillis. Anthony Spinelli's Cry for Cindy gives They Called Her Lisa a run for its money in terms of being suprisingly downbeat but like the similarly excellent Lustful Feelings they are far more melancholy than the cold but very angry They Called Her Lisa.

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