It’s safe to say that David Harbour and Lily Allen don’t shy away from showering each other with affection compliments.

Speaking with PEOPLE for the Sexiest Man Alive 2019 issue, Harbour, who was appointed one of the Men of the Year, divulged one of the best non-work-related commendations he’s ever received.

“Lily Allen once been suggested that I was so fantastic it was an outrage, ” the Stranger Things star, 44, said about his singer-songwriter girlfriend.

And the Stranger Things actor feels the same way about the British musician, 34.

“I really only look at my girlfriend’s gazes, until she’s turned away from me and I stare at her stunningly beautiful backside, ” he am talking about his favorite part of a woman’s body.

When it comes to the most attractive trait he learns in development partners? “A health stomach, ” Harbour said.

For more on the Sexiest Man Alive- and all the hottest chaps in Hollywood- sound here and pick up this week’s issue, on stands Friday, Nov. 15!

Harbour and the “Smile” hitmaker first triggered dating rumors in January, when they attended the BAFTA Tea Party together. Allen, the sister of Game of Thrones ‘ Alfie Allen, revealed in January that she had split from her DJ boyfriend Meridian Dan. The two had been together since 2015.

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Allen and Harbour were recognise all going together in August while he was filming Black Widow in London, where they attended the performance of The Lehman Trilogy at the Piccadilly Theater and then dined at a restaurant. Following his hosting entry on Saturday Night Live in October, the Hellboy actor was photographed heading to the show’s afterparty in New York City with the British singer.

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Allen shared photos from Harbour’s SNL sketch parodying a SoulCycle class, during which the host wore a sleeveless shirt and demonstrated off his muscular forearms. Allen captioned a zoomed-in photo of Harbour’s bicep, “Mine.”

The stars was subsequently clicked locking lips as they trod through wall street of New York City the next day to grab lunch together.

At the end of October, Harbour impelled their relationship social media official by sharing his first-ever Instagram photo of the pair enjoying a date at Disney’s Magic Kingdom in Florida.

Read more: people.com