Taylor Swift once got Harry Styles a birthday present he'll never forget.

According to Australian band the Temper Trap, Taylor approached the group after the 2012 ARIAs to ask for a birthday present for her then-beau: handwritten lyrics to their hit 'Sweet Disposition,' which contains lyrics that the One Direction singer has tattooed on his arm. The only problem? Harry has the wrong lyrics inked -- and the band (and, reportedly, Taylor Swift) knew it.

Frontman Dougy Mandagy explained the situation to Australia's Pedestrian TV (quotes via the Daily Mail), revealing, "Harry Styles has got the wrong lyrics tattooed -- he's got like a portion of the pre-chorus of 'Sweet Disposition' ...but it's wrong." (Harry has "won't stop 'til we surrender" inked on his arm, though the actual lyrics are "won't stop to surrender.")

The rocker recalled how Taylor approached the group at the Australian awards show in November 2012.

"She was like 'Hey,' you know, 'I'm a big fan,'" Dougy explained. "And she goes 'Ahh, it's my boyfriend's birthday soon, I wanna give him a present -- here's a piece of paper, can you please write down the lyrics to 'Sweet Disposition,' sign it, I wanna give it to him.'" Super cool idea, right?

However, knowing that the boy bander had the incorrect lyrics inked, the musician had a bit of a moral dilemma at hand.

"So I had this dilemma in my mind at that point: Do I write the wrong lyrics? Do I write the right lyrics?'" he laughed, ultimately choosing to pen the correct lyrics. "I kept it real, I wrote the right lyrics, man." Still, the drummer joked, "And they broke up soon after."

And according to a Daily Star source, Taylor actually showed Harry the lyrics to prove that she was right.

"Harry didn't have a clue he got the wording wrong until Taylor pointed it out to him," the insider revealed in 2013. "He wouldn't accept he was wrong until she asked the Temper Trap at the ARIA Awards back in November. Harry was so embarrassed he made Taylor promise not to tell anyone but that's all changed now they've split up."

Hmmm. We have a hard time believing that Taylor would be "so casually cruel in the name of being honest," to quote her own song lyrics. (Interestingly enough, 'All Too Well' also contains the phrase "sweet disposition.") But if she were to ever want to make it up to him, now's the time -- Harry's 21st birthday is in just four days.

Swifties, Directioners + Haylor shippers, what do you think of the Temper Trap's revelation?

See How Harry Styles Reacted to Taylor Swift's Songs About Him

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