Kat Dennings Posts Sweet Birthday Tribute for Fiancé Andrew W.K.: 'Sweetest, Most Wonderful Man'

Kat Dennings showed up for fiancé Andrew W.K on his special day!

As the musician turned 43 on Monday, Dennings honored him with a sweet Instagram tribute. Her upload included a close-up selfie of the duo.

"Happy birthday to the sweetest, most wonderful man in the world, who has NO relation to AI-generated Sirius Black," the 35-year-old Dollface alum jokingly wrote. "None. Zero."

Dennings first publicized the pair's romance in May 2021. Later that month, she confirmed that they are engaged.

"Don't mind if I do," she captioned a series of photos, which included a close-up of her stunning diamond engagement ring.

RELATED: The Cutest Photos of Kat Dennings with Her Fiancé Andrew W.K.

The WandaVision actress recently revealed that the couple proposed at the same time.

"We had a special moment that makes me believe in magic," she said on The Drew Barrymore Show in February. "We were doing kissing, and we had, like, a shared feeling. I felt this intense … thing that I was like, 'This is my person. This is it. I can't live without him. This is the man I'm supposed to be with.' And we looked at each other, and we both proposed at the same time."

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Dennings said that the intimate proposal with her beau, whose real name is Andrew Fetterly Wilkes-Krier, was "not planned."

"No knee down — I don't even remember what happened after that," she continued. "We just were like 'Should we get married?' And 'Yes.' I just burst into tears."

Added Dennings, "It was like I never thought I had it in me, you know, because I'm kind of a toughie. But I did. I wept happy tears. I felt this sense of relief that I've done it. I made it through the wilderness and found this incredible person, and yeah. No one believes me. But I assure you, that's what happened."

Kat Dennings/Instagram

Additionally, Dennings said she was happy to have waited until she "found the right person."

Before finding love with her soon-to-be-husband, Dennings dated Josh Groban. But the pair — who were introduced through her former 2 Broke Girls co-star Beth Behrs — split in 2016 after two years together.