Justin Bieber and One Direction's Niall Horan Hung Out Together, and the Fans Almost Couldn't Take It

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What happens when you combine two of the most dedicated fandoms ever?

Justin Bieber and One Direction's Niall Horan decided to find out Sunday night, when the two 21-year-old heartthrobs spent some quality bro time together. Throw in 18-year-old Cody Simpson, and you can imagine how the blonde-haired trio was just too much for all of their fans.

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Check out this video of the three singing together, with Cody on guitar.

And here they are posing with a few excited gals.

Not surprisingly, plenty of people had the appropriate freak out on Twitter.

Let's recall when Niall and Justin met for the first time in 2010.

And Niall covering Bieber's 2009 hit "One Time."

Friendship goals!

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Justin shocked his fans just last week, starring in his creepiest photoshoot ever for Interview magazine, in which he posed with a knife and in a terrifying clown mask. Watch below:

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