“Taylor Swift wrote “This Is What You Came For” under the pseudonym Nils Sjoberg,” the singer’s rep confirms exclusively to PEOPLE.
Earlier on Wednesday, TMZ reported that Swift “wrote the song, sat down at a piano and did a demo into her iPhone,” which she then sent to Harris.
“Lightning, this is what you came for / Lightning strikes every time she moves / And everybody’s watching her,” read the lyrics. “We go fast till they can’t replay / Who knows why it’s gotta be this way / We say nothing more than we need / I say “your place” when we leave.”
After recording a full demo, they agreed to keep the collaboration on the down-low, but Swift was hurt after Harris did an interview and said he couldn’t foresee working with his then-girlfriend in the future.
“You know, we haven’t even spoken about it. I can’t see it happening though,” Harris told Ryan Seacrest while promoting the song.
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After meeting Tom Hiddleston at the Met Ball in May, Swift’s friendship with the actor took a romantic turn weeks after her split from Harris, and the new couple have been globe-trotting in the last month.