How crazy fast did Pete Davidson know he wanted to wife Ariana Grande? From Day 1

Pete Davidson can attest to the old adage: when you know, you know.

Ariana Grande's fiancé opened up to GQ about their whirlwind romance for the magazine's September issue.

Still feeling like "the luckiest guy in the world," Davidson said he knew he wanted to commit to Grande pretty much at first sight.

"The day I met her, I was like, 'Hey, I'll marry you tomorrow,' " the "Saturday Night Live" cast member recalled. "She was calling my bluff." But Davidson was not messing around.

"I sent her a picture (of engagement rings)," he said. "I was like, 'Do you like any of these?' She was like, 'Those are my favorite ones,' and I was like, 'Sick.' " Sick!

Davidson confirmed the two were engaged on "The Tonight Show" in June after they made things Instagram-official in late May. Though Davidson says wedding plans haven't quite come together, he insists their walk down the aisle is "definitely going to happen, for sure."

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Also on their agenda? Furnishing their new apartment in Manhattan, which Davidson said Grande purchased. Davidson takes it upon himself to keep their fridge stocked – with grande-sized drinks, we presume.

"She's really sweet," Davidson said praising his love. "She's like, 'This is our house,' and I'm like, 'You're very nice for saying that. Thank you for letting me stay here.' "

"She's like, 'We're getting married!' " he added. "And I'm like, 'I know, thank you for letting me stay here.' "

But their digs filled with love seem to be filled with little else. "It's like, we have six beanbags, but we have no forks – you know what I mean?" he said. "We're learning how to be adults. We're having a really fun time." 

Sigh... that's all that forking matters.

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