It was fast food that got sparks flying between Katy and Orlando the night they met at a Golden Globes after party in January 2016.
"We bonded over an In-N-Out burger about three years [ago] at the Golden Globes. He stole one off of my table," Katy told Jimmy Kimmel in 2019.
"He took it, and I was like, 'Wait! Who — oh, you're so hot. Fine, take it!' And then I saw him at a party, and I was like, 'How are those onions resting on your molars?' He's like, 'I like you.'"
Despite attending Coachella music festival together, the couple didn't make their relationship Instagram official until May that year, when Katy shared a picture to Instagram of herself and Orlando lying on some steps in Cannes, France with the punny caption: "We Canne't."
Later that year, the couple found themselves at the centre of a nude photo scandal when a naked Orlando was snapped by paparazzi on a paddleboard with Katy.
In February 2017, however, the fairytale romance appeared to end when the couple revealed they'd broken up to Entertainment Tonight.
"Before rumours or falsifications get out of hand, we can confirm that Orlando and Katy are taking respectful, loving space at this time," the statement said.
Shortly afterwards, Katy shared a tweet alluding to her break up that said: "HOW BOUT A NEW WAY OF THINKING FOR 2017?! U can still b friends & love ur former partners! No one's a victim or a villain, get a life y'all!"
Orlando also commented on the split in an interview with ELLE, explaining that he and Katy were still friends.
"We're all grown-up. She happens to be someone who is very visible, but I don't think anybody cares what I'm up to. Nor should they. It's between us. It's better to set an example for kids and show that [break-ups] don't have to be about hate".
Thankfully, by April 2018 Katy and Orlando were back on and were all loved-up at their first red carpet appearance five months later.
In the ultimate romantic move, Orlando popped the question to Katy on Valentine's Day 2019 with a flower-shaped pink diamond ring that the bride-to-be showed off on her Instagram account.
Speaking with Roman Kemp on Capital Breakfast, Katy spilled details about the proposal three months later.
"It was Valentine's Day and I had to work that day," she recounted. "I just remember meeting him at dinner at this place, this Italian restaurant, because when I get a pass, I just want to stuff my face with pasta. So I get there and, I mean, he's like clean-shaven. He's not wearing tennis shoes. I'm like, 'Ah s---, something is going down!'
"I got on a helicopter and he asked me to marry him, and then we landed on this building and then went downstairs and my family and friends were there and the most flowers you've ever seen."
In her cover story for Vogue India, the Roar singer confessed that while Orlando isn't the number one Katy Perry fan, "he's the number one fan of Katheryn Hudson" - her real name.
"Orlando is like a sage. When we first met, he said we would pull the poison out of each other, and we really do," she told the publication.
"It's exhausting, but we really hold each other accountable. I've never had a partner who was willing to go on an emotional and spiritual journey like Orlando. It's challenging, because you're facing all the things you don't like about yourself. It's like a never-ending cleanse."
Katy then revealed that she was pregnant with her and Orlando's first child in the music video for her song Never Worn White.
She is due to give birth to their daughter in the US summertime.
The parents-to-be are "yet to decide specifically" on their daughter's name, but Katy says that Orlando, who shares son Flynn with ex Miranda Kerr, is "really excited" to welcome a daughter.
"I think he's really excited for a little girl. They say that little girls are, you know, daddy's little girl. That's how it's going to be. We'll see," she said.
Congratulations to the happy couple!
