» Back to the two Swifties directly in front of me during the concert. I attended the party with my father and brother-in-law, and when Swift went into an acoustic rendition of "This Is What You Came For" -- the song she infamously co-wrote with ex Calvin Harris -- I turned to my Dad and said, "This is a cover of a big Rihanna song." This prompted the teen Swiftie to turn around and hiss, "She wrote the song." "She" meaning Taylor Swift, though I'm sure you could have guessed that.