Camila Cabello and Shawn Mendes may not be dating, but their friendship — and total BFF status — hasn't been going on for as long as you'd think! Even though they both opened for Austin Mahone on his tour in 2014, they didn't become pals until a few months ago.

"I honestly remember so clearly the first day we met. He was just playing with a guitar, and I was like, 'Hi! Nice to meet you.' We didn't really hang around much during Austin's tour. It was Shawn's first tour ever, so he was constantly working, and if he wasn't working, he was in his bus playing guitar and being a loner," Camila told Rolling Stone.

CLICK HERE FOR 14 REASONS SHAWN MENDES & CAMILA CABELLO BELONG TOGETHER!

However, they reconnected at one of Taylor Swift's concerts, when he was opening on The 1989 World Tour.

She said, "That was the first time we had ever really spent more than a few minutes talking to each other."

Then, while they were chilling, they started writing "I Know What You Did Last Summer."

"We were just backstage hanging out. I pulled out my guitar and we were just messing around, not really thinking about writing a song," he said.

And the rest is history! Now we have a beautiful friendship and a great song to show from it.

MORE: SHAWN MENDES & CAMILA CABELLO FOUGHT WHILE WRITING "IKWYDLS"

Are you surprised they didn't really hang out on Austin's tour? Are you glad they're friends now? Sound off in the comments!

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