The perhaps unlikely pair have been pals since meeting backstage at a US talk show last year, and on Thursday night Kim was among the thousands of fans watching Sam perform at The Forum in LA.
Kim, 34, dressed to impress in a cleavage enhancing zipped black bustier and skirt, topped with a furry gilet and absolutely enormous diamond earrings.
Before joining siblings Khloe Kardashian, Kendall Jenner and pal Cara Delevingne in the crowd, Kim popped backstage to wish Sam luck – and get a picture for Instagram, of course!
Looking very smart, Sam!
He posted the picture to his Instagram as well, alongside the caption: "Thank you for coming beautiful human." Aww.
During the concert, the siblings and their pals posted a multitude of pouty pictures from the audience as they enjoyed his performance.
Afterwards, the merry gang headed backstage to sip some celebratory bubbly with Sam himself and get even more photos!
The Kardashians and Cara weren't the only stars in the audience to support Sam: the legendary Chaka Khan was also there. Sam later said: "I adore you Chaka Khan! Amazing to see you and thank you for the fan gorgeous haha."
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