Justin Bieber made a surprise appearance during an Ariana Grande concert in LA last night, and the Biebs being the Biebs, he got a little handsy with the main attraction. 

As you can see in the video below, Ariana was clearly not enjoying Justin's advances.

Posted in: Justin Bieber

Ariana Grande has only been an A-list pop star for a few months, but she's reportedly already developed certain diva-like habits.

Insiders say Ariana insists on being photographed on her left side, she has insanely specific hair and makeup demands, and even instructs production crews on what sort of light they should use when they film her.

Posted in: Mariah Carey