Nick Jonas & Nina Dobrev Celebrate Demi Lovato's 'Sorry Not Sorry' in Las Vegas

Nick Jonas and Nina Dobrev were just some of the stars who helped Demi Lovato continue her House Party Tour last night!

The 24-year-old “Jealous” singer and the 28-year-old Vampire Diaries star snapped this pic with Demi on Friday (July 14) in Las Vegas.

PHOTOS: Check out the latest pics of Demi Lovato

They were joined by Nina‘s new boyfriend Glen Powell, Wiz Khalifa, and Diplo.

Demi took the stage with The Chainsmokers at XS to perform her new single “Sorry Not Sorry.”

“Love you guys!!” Demi shared on Instagram. “Thank you always for your support and inviting me to hop up on stage with you last night @thechainsmokers.”

Demi kicked off her House Party Tour earlier this week at a mansion in Boston, Mass., with New England Patriots player Rob Gronkowski!

Demi will visit seven cities during the tour and will include a new local celeb at each show.

10+ pictures inside of Demi Lovato, Nick Jonas, Nina Dobrev, and more at the show…