Sally Darson is a fourth grade student at South Park Elementary. She sells kisses behind the temp building at recess. She'll kiss any boy that pays her. Basically, she's an elementary version of a prostitute.
When Butters gets the idea to bring her business to a bigger potential, she becomes his Bottom Bitch in his business.
Sally reveals she has swimming practice in the mornings, alluding to the existence of a South Park elementary swim team. She is the only know member.
After Butters pays her five dollars to kiss him, he begins to let other boys know about her business. To thank him for bringing in customers, she gives him a two dollar cut. After this, Butters brings up the idea of expanding her business by hiring other girls to be apart of it. His next idea is to charge two dollars for a hug along with the five dollar kisses. When Butters decides to leave the business at the end of the episode, is it unknown if Sally has kept up with the business.