The Queen of Sin (2018) on Netflix

Plot summary

Posy Pinkerton is in her late twenties and has always moved from one steady relationship to the next. Her life looks settled: Tom, a doctor, is her fiancé, she draws medical illustrations for a living, and she paints on the side. Then a chance meeting with Jack, a well-traveled businessman, leaves her wanting more. She tells herself the flirtation will go no further than that, but her cousin Laura, who is nothing like her, argues for a last fling before the wedding. The freedom Posy has been craving finds a name, an alter ego she calls the Queen of Sin. What began as a fling may be a bargain with something darker.