Shannon is a member of of an abstinence group that Steve falls for in "My Purity Ball and Chain".
Francine belives it is time for Stan to talk sex with Steve after they observe him performing an unnatural act on a broom. Stan is reluctant due to poor teaching by his own father Jack Smith. When Steve is forcibly volunteered to participate in the abstinence program at school, Shannon tells him afterwards that she enjoyed his performance and gives him a group flier. When Stan discovers the flier, he believes it to be his ticket out of giving the sex talk in addition to getting to wear a sword with the other fathers. When Steve and Shannon start getting too close to each other, Stan tries to keep them apart. But when they are discovered holding hands under a fallen banner by Shannon's father Michael, the other fathers threaten to kick the pair out unless Steve attends Sex Aversion Therapy Camp.
Steve is so traumatized by the camp that he can no longer even look at girls without becoming nauseous at a purity ball. When Stan realizes what he has done, as well as seeing that the other fathers are really creeps in "dating" their own daughters, he shuts Steve and Shannon alone in a broom closet and fends off the other sword-wielding dads, while giving Steve his own version of a sex talk. He succeeds long enough for the pair to score at the price of becoming severely injured.
Although her name is only given as "Shannon" in the episode, she was given the last name of "Wells" after her voice actress in a promo image released on Facebook roughly a month after the episode aired. It also implies that Steve and Shannon actually had sex.
Shannon is voiced by Noël Wells.