She wears black and red underwears that includes corset and white undies. She has some jester tattoos on her left arm and fingerless gloves. Her face appears to have white and black make up as well stitches on her neck. Her hair has same colors as Harley Quinn's jester hat.
Upon kidnapping and mutilating several innocent people, she uses the corpses as various toys, dolls, and mannequins. When Batman arrives to save a victim, he fights and defeats her after she cut herself with an chainsaw. She admits defeat, but ends up getting killed as Batman reveals himself to be a vampire and ends up biting her neck in order to drink her blood.
- Like Harley Quinn, she was voiced by Tara Strong.
- According to Bruce Timm, Harlequin's similarities to Harley Quinn were deliberate, as the similarities as well as his having her killed by Batman were as a way of getting back at the New 52 for their redesign of Harley Quinn.
- She is considered to be the darkest version of Harley Quinn of all time, presumably at the level of the Joker.
- In her fridge, she has besides severed limbs a drink called Grape Soder.