Sometimes the best movie stories are ones that come from real life – even if it involves a romantic glass of…milk.

Yes, milk. That’s what drives Harris Dickinson’s character in the new erotic thriller “Babygirl” to Nicole Kidman’s character drinking in a bar in the midst of their spicy romance, an experience that happened to her in real life, according to the film’s director, Halina Reijn.

In the scene, Samuel (Dickinson), Romy’s (Kidman) much younger intern and her lover, orders Romy a glass of milk from across the bar. As she drinks it, Samuel says “Good girl” to her as he leaves the bar.

“The milk is of course an archetype,” Reijn said in an interview with IndieWire published Saturday. “We’ve seen it in other films. It’s a great symbol of the animalistic sides of ourselves. It happened to me.”

Reijn went on to describe her own encounter. She said it happened to her years ago in Belgium when she went to a bar alone and met a “young Belgian actor” who she didn’t name but who was famous and “at least 15 years younger than me.” .

“He ordered me a glass of milk. I thought it was an incredible, hot thing and so brave, and so I wanted to reward him by drinking the whole thing, and that’s what I did,” she said.

While Reijn admitted that she felt “a little nauseous” from drinking the milk, she “believed it was one of the most arousing moments of my life” while writing the script for the film.

She added that the mystery actor didn’t say “good girl” to her like Samuel tells Romy in the film.

“I wish he had,” Reijn said. “He just walked out.”

Released on Christmas Day, Babygirl follows Romy, a powerful CEO who has a torrid affair with her much younger intern Samuel. Kidman, Dickinson, Antonio Banderas and Esther Rose McGregor star.

Cheers…we guess?

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