Crystal and Clay Duffy are a married couple who are into swinging with other couples. They are an attractive couple of blond upper middle class yuppies who don't want kids, they are only interested in swinging. They have slept with a surprisingly large amount of Quahog's married couples, being the most active swingers in the game. However, they were uninterested in swinging with Peter and Lois Griffin and only wanted to be friends with them, much to their chagrin.