However, instead of striking up conversation, the father-of-one admitted he was completely starstruck and “just stared at her”.
“I was just that creepy guy in the corner,” he added.
Nat jokingly asked if he had any urges to “pinch her on the bottom” to see if it was real.
“I would never dream of doing that,” Matty protested.
“And she had two big bodyguards who were pretty scary-looking so I kept my distance.”
At this point, Nat admitted that she too had once met Kim – as well as her sister, Khloe - when she was filming The X Factor.
'I met her as well and I thought she was just so much smaller than we think,' Nat said, before going on to explain that Khloe was very outgoing, while Kim was quiet and shy.
“They were all really sweet, really lovely.”
Matty J also weighed in on the split rumours surrounding current Bachelorette winners Angie Kent and Carlin Sterritt.
“The breaking story is, ‘oh my gosh, they're in love" and then that narrative can only play out for so long before someone has to throw some salacious rumours in the mix,” he said during a conversation on The Babble.
Listing all the potential rumours, Matty – who celebrated the birth of his first child with fiancée Laura Byrne earlier this year – said pregnancy rumours would be next.
“First, they're amazing. Then there's stories of they didn't want to pick anyone and ‘are they still together?’ And then the next rumour that will come out is that Angie's pregnant,” he said.
Matty went on to state that he believes that Carlin and Angie are still together and said it was “lovely to see".