The lips in the opening credits belong to Santana, the song she sings also happens to be her first solo.
The two suits who visit Sue are played by Barry Bostwick and Marvin Lee "Meat Loaf" Aday, who played Brad and Eddie, respectively, in The Rocky Horror Picture Show (1975).
Jayma Mays, who plays Emma, sings "Toucha, Toucha, Touch Me" in this episode. That was the song she auditioned for the show with.
Sue says that she took her sister to a midnight "Rocky Horror" showing once and complains that "the audience was so enraged there was a disabled person in the audience that they threw toast at us." Throwing toast is one of the many standard audience participation features of all midnight screenings of The Rocky Horror Picture Show (1975); Sue took something personally that would have happened regardless of her or her sister's presence.
This is the first episode with an on-screen title.