Chloe Grace Moretz and her boyfriend, Brooklyn Beckham, made their official red carpet debut at the premiere of her new film, Neighbors 2, and the young actress couldn't help but gush to ET about her "good boy."

The cute couple shined on the red carpet at the Regency Village Theatre in the Westwood neighborhood of Los Angeles, California on Monday. Moretz wore a skin-baring semi-sheer black gown with a plunging neckline while Beckham rocked a tux jacket and jeans combo.

WATCH: Chloe Grace Moretz Finally Confirms Her Relationship With Brooklyn Beckham

"He's a sweetie," Moretz shared with ET's Nischelle Turner at the premiere. "He's a good boy!"

The 19-year-old actress and the 17-year-old photographer -- who happens to be the son of David and Victoria Beckham -- just confirmed their relationship earlier this month.

WATCH: Brooklyn Beckham 'Hearts' Chloe Grace Moretz in Cutest Instagram Pic Ever

Moretz opened up about her relationship with Beckham, revealing that they met "a long time ago, years ago."

"I think [we met] at SoulCycle or something random," Moretz said, laughing. "That's how it is! Every Hollywood love story [starts] at SoulCycle."

NEWS: Brooklyn Beckham and Chloe Grace Moretz Show Some PDA

Moretz first opened up about dating Beckham last Monday while sitting down with Andy Cohen on Watch What Happens Live, where she admitted, "I think the more I don't make it mysterious, the more people don't care, so yes, we're in a relationship."

For more on her sit-down with Cohen, where she also dishes on what she thinks about her boyfriends' famous parents, check out the video below.

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