Betty is the owner of Betty's Magic Emporium in Port Sarim. She is one of the only two characters selling eyes of newt in free-to-play worlds, the other being Poletax. Lottie, her assistant, stays under her shop.
Betty plays a vital role in the Witch's Potion miniquest, and is a character in The Hand in the Sand quest helping in creation of pink dye. She is also involved in While Guthix Sleeps, the 2008 Hallowe'en event and plays an important role in the Swept Away quest.
She is involved in one of the hard Falador Tasks: Dye a cape pink with pink dye from Betty in Port Sarim.
According to Maggie, Betty "is the perfect witch to take care of the wand-waving part of the package."