by Lavigne's era of pop punk and MGK took his new pink hair out for a public reveal. Fox had her silky black hair up in pigtails, and wore a low cut black crop top with thin mesh covering her décolletage. Her black pants matched her zippered jacket.

For accessories, she carried a small black handbag on a chain, wore flawless makeup, and neon green nails. MGK was in a graphic pink and black t-shirt cropped to show his abdomen and full-sleeve tattoos over a pair of black cargo pants covered in zippers. His large black and green combat boots were loosely laced with pale pink shoelaces.

Machine Gun Kelly was featured on Lavigne's new album Love Sux and he briefly stepped up on to the stage with her to promote his appearance on her second track, “Bois Lie.”

The song was co-produced by his friend, musician Travis Barker, who attended the concert with his fiancée Kourtney Kardashian. MGK also congratulated Lavigne on her new album on Twitter, writing, “congrats on the album @AvrilLavigne !! i can’t believe i’m on it, Bois Lie was so fun to record — video soon.”

Also in attendance was Willow Smith and a plethora of other celebrities. Lavigne was clearly having an amazing time on stage, letting her long straight blonde hair with a bright orange ombre hang down over her off-the-shoulder black top.

Like Barker and Kardashian, Fox and Kelly are recently engaged and are planning their upcoming wedding. After proposing, MGK posted a photo of the custom-designed wedding ring made with a diamond and emerald to symbolize their birthstones.