Demi Lovato & Billie Eilish Meet Some 'Bad Guys' at Halloween Horror Nights!

Demi Lovato and Billie Eilish get their scare on at Halloween Horror Nights!

The 27-year-old “Echame la Culpa” singer and the 17-year-old “bad guy” crooner visited Universal Studios Hollywood on Sunday (October 27) in Universal City, Calif.

Demi posed with a group of chainsaw-wielding demons, while Billie Eilish got spooked by a couple of “bad guys.”

“It’s not Halloween unless you go to @horrornights at Universal!” Demi shared on Instagram. “Thank you #UniversalHHN for the tricks & treats with some of my favorite people 🎃🖤👻 always a blast.”

Singers Jessie J and Trevor Jackson were also in attendance that night.

Get a closer look at all of the photos in our gallery.

The night before, Demi Lovato hosted her fourth annual Halloween party dressed as Pennywise. See the pics!