Halsey and Avril Lavigne Dress Up 'Girlfriend' For Ultimate Halloween Duet: Watch

Marilyn Manson and Madonna teamed up for a killer cover of Avril Lavigne's 2007 hit "Girlfriend" over the weekend at Halsey's annual Halloween bash. Okay, Halsey, dressed as Manson, and Lavigne, in her finest Madonna gear drove the crowd nuts with their surprise duet on Avril's iconic track while sporting two classic looks.  

Halsey, wearing an all-white ensemble that perfectly captured Manson's Mechanical Animals look, looked super pumped to be singing alongside Lavigne, decked out in lots of black lace, leather and rocking giant hair.