Anya first appears in "The Wish" (3.8) as the vengeance demon Anyanka. Giles destroys her power centre - her amulet - and her superiors (D'Hoffryn in particular) refuse to change her back - Anya is stuck in Sunnydale as a mortal.

She lies to Willow about her necklace, saying it's a family heirloom, and asks her to get it back with a magick spell. But something goes wrong, and evil Vamp Willow who lived in the alternate reality of "The Wish" appears.

Anya is now stuck in this reality without her powers, so she begins to make adjustments. For one thing - she invites Xander to the prom, where she regales him with tales of her exploits, including making men's heads explode and "parts fall off". She also shares with the others everything she knows about the Ascension, having lived through it, including the fact that she for one is getting out of town as fast as is ex-demonically possible.

She reappears in "The Harsh Light Of Day" (4.3) ready to seduce Xander so she can get him out of her mind. Unfortunately, the plan fails, and she and Xander begin dating. They have their first date at the haunted house in "Fear, Itself" (4.4) - when xander tells her to dress in something scary, she turns up in a pink bunny suit, because rabbits scare her!

The former demon's lack of discretion makes for many comical moments - when she announces to the group that she has "four K-cards" in poker, both Xander and Willow glumly fold, and when Willow mentions that Buffy has "a spanking new boyfriend", she replies that she and Xander have enjoyed spanking. She also states that Thanksgiving is "a ritual sacrifice. With pie.", and tells Giles that Olivia is his "orgasm friend", to which the librarian's response is "Yes, that's exactly the most appalling thing you could have said."

So far, Anya has primarily acted as a foil for Xander's antics, helping in rituals but not initiating much action. Though she has not been a core member of the Scooby Gang, the fact that she appears in "Restless" (4.22) shows that she is on everyone's minds, and has begun to be a character in her own right (see "Where the Wild Things Are" (4.18) and her stand-up routine in "Restless" (4.22)) showing that the Slayerettes have started to accept her.

Anya is played by Emma Caulfield.