Halsey and Evan Peters Transform Into Sonny and Cher for 'AHS' Red Carpet Debut

American Horror Story star Evan Peters and singer Halsey picked the perfect time to make their relationship official. The two walked the red carpet dressed as Sonny Bono and Cher at the American Horror Story 100th Episode Celebration in Los Angeles Saturday. On Friday, the two attended Halsey's Halloween party together, with Halsey sharing photos of their costumes on Instagram.

On Saturday night, Halsey dressed as Cher while Peters dressed as Bono, complete with a fake handlebar mustache. Halsey wore a polka-dot dress, matching the polka-dot shirt Peters wore under his white jacket.

The night before the couple made their red carpet debut Halsey took Peters to her Halloween party. The "Without Me" singer dressed as Marilyn Manson, complete with a red wig and a skin-tight white leather outfit. Peters dressed as a Juggalo, a fan of the group Insane Clown Posse.

Halsey shared photos of their outfits on Instagram, adding, "Resident goths" in the caption.

Peters, 32, and Halsey, 25, have been linked since they were seen on a date at Six Flags Magic Mountain in Los Angeles on Sept. 21. A witness told PEOPLE the two were "flirting" while they were in line for the Goliath rollercoaster.

The new relationship started after the two stars both ended longterm relationships. Halsey was linked to British musician Yungblud for a year before they broke up earlier in September.

"It was sort of abrupt and it was Halsey's decision to end the relationship. Halsey has been very busy with her work commitments and traveling a lot recently, and their relationship was getting rocky," a source told E! News. "She's been very busy and focused on her career, which took more of a priority."

Meanwhile, Peters was engaged to his American Horror Story co-star Emma Roberts until they broke up in March.

"Halsey has always been a huge fan of Evan's," E! News' source explained. "A friend connected them and they had also been chatting over social media before deciding to hang out. It's still very new, but they are both interested in dating each other and hanging out."

Peters rose to prominence as Quicksilver in the X-Men movies and has played multiple roles in the American Horror Story seasons. Although he does not star in American Horror Story: 1984, he does appear in Ryan Murphy's Pose as Stan Bowes.

As for Halsey, she will be releasing her third album Manic on Jan. 17. The album will include the singles "Clementine," "Graveyard" and "Without Me." She also announced a world tour that will begin in Europe in February to support the album.

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