Mila Kunis attended the 2018 Billboard Music Awards at the MGM Grand Garden Arena in Las Vegas alongside several other celebrities.

However, she became popular years ago for her portrayal of Lily, a rival ballet dancer, in the psychological thriller “Black Swan.”

Kunis had to lose weight for the role, but she claims that she did it in the healthiest way possible.

In an interview on Howard Stern’s SiriusXM show, Kunis revealed that she never starved herself before but had to do it for “Black Swan.”

“I had to look skinny to look like a ballerina,” she explained. She did it by using a food delivery service and smoking.

She admitted that it was an awful experience and wouldn’t recommend it to anyone.

Director Darren Aronofsky cast Kunis after seeing her in the 2008 American romantic comedy film “Forgetting Sarah Marshall.”

Aronofsky would tell the two actresses things about each other to make them jealous and create a real-life rivalry between them.

However, they became friends instead. Portman shared with US Weekly how they would watch Top Chef together on their “sweatpants nights,” and they would end up on the set in tutus, emaciated and tired.

Portman admitted that she didn’t think through the fact that she was going to have a lesbian s^x scene with Kunis in the movie.

It ended up being awkward for both actresses.

“It almost feels like it would be easier to do it with someone you didn’t know,” she told MTV.

Kunis revealed that there was no alcohol involved in the scene and that they wouldn’t have been able to do it intoxicated.

In addition to the lesbian s^x scene, Portman also shared an on-screen kiss with Kunis in “Black Swan.”

When asked by Andy Cohen on “Watch What Happens Live,” Portman said that Kunis was the better kisser, obviously, than her “No Strings Attached” co-star Ashton Kutcher.

Despite being friends, the intimate scenes were still uncomfortable for the actresses. Portman said that it didn’t matter whether it was a friend or a male or a female.

“You’re with 100-something crew members, lighting you, repositioning you, there’s no comfort whatsoever,” she told reporters on the red carpet.

Kunis attended the 2018 Billboard Music Awards with a new hairstyle and rocked a black and silver crystal-embellished cady skirt from David Koma’s Fall 2017 collection, which costs $2,125.

Despite the high price tag, it’s still more affordable than Jennifer Lopez’s $85,070 Roberto Cavalli crocodile creation.

Kunis paired the skirt with a black long-sleeved crop top from the same collection.

However, some people wished that she had opted for a more edgy pair of shoes.

They suggested the floral-embellished stiletto sandals available for purchase for $10 at ShoeDazzle.

The movie “Black Swan” was a huge success, and Portman won an Oscar for her performance. She also met her husband, Benjamin Millepied, on the set of the film.

It was an intense experience for both actresses, but it led to a beautiful friendship.