The pop world is so small, and the proof lies in the fact that pop stars are always hanging out with each other. A recent example: Niall Horan and Ariana Grande were both in the same club in London last night (June 1), immediately following Ariana's first UK show at the O2 Arena on her current world tour.

Although there are no photos of the two of them actually hanging out together, they were both reportedly seen at Cirque Le Soir in central London. You can check out photos of Ariana and her signature ponytail, as well as Niall's weird obsession with gross newsboy caps, over at the Daily Mail.

We initially weren't sure if this was mere tabloid fodder, because there's no photographic evidence of the two interacting at the club -- and seeing is truly believing. But a video eventually surfaced online, confirming that the rumors are true: Niall and Ariana did breathe the same air at some point — or to be more accurate, the same gas. Ariana posted a low-quality video to Instagram depicting a batch of large pixels that, when viewed through heavily squinted eyes, take on the appearance of Niall, Ariana and two friends. The subjects of the video appear to be sucking on a helium balloon, manipulating their voices without the aid of Auto-Tune (as was once the way of the world). They're having so much vintage-style fun here that Niall's newsboy cap suddenly looks appropriate.

You can check out the video above, and be sure to keep the sound on so you can hear a squeaky-voiced Ariana say what sounds like, "I could make a broke bitch rich." You probably could, Ariana.

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