Lauren Jauregui & Boyfriend Ty Dolla $ign Join Adam Lambert at Halsey's Halloween Party!

Lauren Jauregui and Ty Dolla $ign channel Harley Quinn and Joker at Halsey‘s Halloween Party!

The 22-year-old Fifth Harmony member and the 33-year-old “Sucker for Pain” singer stepped out for the event held at The Majestic Downtown on Friday (October 26) in Los Angeles.

PHOTOS: Check out the latest pics of Lauren Jauregui

“Daddy’s Lil Monster👅👅👅,” Lauren captioned the Instagram slideshow below. “Harley Quinn & The Joker take Gotham City🍸 … New song #Expectations out now too if you’re looking to get in a Halloween vibe(; #linkinbio LaurenJauregui.com.”

“Zad and Mom 😈,” Ty added.

They were joined by Adam Lambert, who dressed up as a devil.