Camila Cabello and Shawn Mendes' "I Know What You Did Last Summer" was one of the catchiest songs of last year, but the Fifth Harmony singer is opening up about the dark side of their collaboration. She says that it was extremely difficult watching fans criticize her and accuse her of trying to go solo. In fact, the pop star insists that "IKWYDLS" was very spontaneous and not a calculated "career move."

"It's been so difficult to watch people criticize me and my intentions. It's been s****y. They turned me [doing the song] into a conspiracy theory. We literally just wrote a song backstage, and it ended up becoming something awesome. It wasn't a career move that I carefully planned out," she said in a recent interview.

As for those dating rumors? Again, a million times again, they are not dating. They are just good friends.

"Shawn and I are great friends. That's why we write so well together — we have fun!"

Um, we can tell!

MORE: 14 REASONS WE SHIP SHAWN MENDES AND CAMILA CABELLO

Click through the gallery to see more photos of them together, and let us know if you want them to write more songs together in the comments!

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