‘Very cuddly’ Ariana Grande and Ethan Slater flaunt romance at Las Vegas ‘Wicked’ party

What happens in Vegas doesn’t need to stay in Vegas, in Ariana Grande and Ethan Slater’s case.

The lovebirds’ affection for each other was on full display at a CinemaCon party in Las Vegas, Nev., after they showed off their new film “Wicked” on Wednesday.

Grande and co-star Cynthia Erivo presented the film at CinemaCon. WireImage

Grande and Cynthia Erivo presented the film at CinemaCon, where Hollywood studios show off their upcoming blockbusters to movie theater owners.

But gobsmacked industry sources told us they were shocked to see Slater taking the lead at an afterparty at Sin City celebrity sushi spot Nobu.

We’re told the couple was flaunting their love, as Slater “was leading her through the party by the hand. He was taking the lead,” a source told Page Six.

Our source described Grande and Slater as “very sweet” — and emphasized they were “very cuddly” throughout the evening.

Slater and Grande have been spotted in Vegas promoting “Wicked.” Brian Prahl / SplashNews.com

Grande seemingly addresses their relationship in her song, “Yes, and?” AFP via Getty Images

We figure Grande took her own hit “Yes, And?” to heart, which includes such lyrics as, “Now I’m so done with caring / What you think, no, I won’t hide,” and, “Come on and walk this way through the fire (don’t care what’s on their mind).”

The studio didn’t seem to be bothered either by the couple’s controversial off-screen relationship, according to sources at the party.

“I thought they’d downplay [their relationship] for promotion. The studio [Universal] doesn’t seem worried. [Grande and Slater] were incredibly affectionate and sweet,” the source said.

Grande and Erivo co-star in the upcoming movie musical. AFP via Getty Images

Grande and Slater “completely blindsided” his wife, Lilly Jay, when they started dating last summer after working together on “Wicked.”

A source described the situation as “horrible” at the time, telling Page Six, “They were high school sweethearts. They have a baby! She’s a wreck.”

Production sources from the film also told us Lilly Jay would visit Slater on the set with their baby at the time, and Grande would spend time with them.

The duo presented the movie to national theater owners in Las Vegas. WireImage

They reportedly even went on double dates with Grande and her ex-husband, Dalton Gomez.

The pop star, who has an estimated net worth of $240 million, had to make a onetime payment of $1.25 million to real estate broker Gomez, with no future alimony, according to reports, when they settled their divorce in March.

Grande has, so far, not commented on her new relationship, but has let her music say it all.

The “Wicked” stars are reportedly shacking up together, happily ever after, in NYC.