Emma Caulfield ( born Emma Chukker in San Diego , California on April 8 , 1973 ) is an American actress . She is best known for her role as ex-demon Anya on the television series Buffy the Vampire Slayer . Emma Caulfield ( born April 8 , 1973 ) is an American actress best known for her role as ex-demon Anya Jenkins on the television series Buffy the Vampire Slayer , as well as Susan Keats , a love interest of Brandon Walsh 's on the television series Beverly Hills , 90210 .