David Harbour Posts First Instagram Photo with Lily Allen: 'The Prince and Princess'

David Harbour has made his relationship with Lily Allen Instagram official!

On Monday, the Stranger Things actor, 44, shared his first-ever Instagram photo of the pair enjoying a day at Disney’s Magic Kingdom in Florida. Seemingly in the spirit of Halloween, which is just days away, the A-list pair wore costumes at the amusement park.

Their ensembles of choice for the Disney day? A prince and princess!

“The prince, princess and the parking lot,” he captioned the mirror selfie of the pair, in which Allen’s face is turned away from the camera. “That seven dwarves mine ride is the best one in the whole damn park. Go on, fight me. #magic #disney #rulebreakers.”

In the snapshot, taken nearby a parking area, Harbour faces the mirror and appears to sport a mullet wig, sunglasses and a blue and gold-colored cape, which channels the beast from Beauty and the Beast. As for Allen, 34, who Harbour tagged in the image, she opted for a pink and purple princess dress, which was paired with pants and sneakers.

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His Instagram post comes more than a week after they stepped out together to attend The Skin Cancer Foundation’s Champions for Change Gala at the Plaza Hotel in New York City.

Allen — the sister of Game of Thrones’ Emmy-nominated actor Alfie Allen — wore a high-neck floral-patterned dress featuring three-quarter sleeves and a pink ribbon around the neckline. She finished the look in black boots and a pair of hoop earrings, with her hair tied half-up.

Harbour looked dapper in an all-black suit with shiny matching shoes as he posed for pictures alongside his date and other stars like Katie Holmes and Sebastian Stan.

Harbour — who previously dated Fantastic Beasts star Alison Sudol — and the “Not Fair” hitmaker first sparked dating rumors in January, when they attended the BAFTA Tea Party together.

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They were spotted together this past 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, according to E! News.

Following his hosting debut on Saturday Night Live, the Hellboy actor was photographed heading to the show’s afterparty in New York City with the British singer.

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

The duo was then snapped locking lips as they walked through the streets of New York City the next day to grab lunch together.