House says, "35-year-old male, he cries blood, and he's not Vampire Bill," referring to the TV series True Blood (2008), based on Charlaine Harris' The Southern Vampire Mysteries. Bill Compton is the vampire romantically involved with Sookie. He is closer to humans than many vampires and weeps tears of blood on occasion. Karolina Wydra, who plays House's wife Dominika, later appeared in True Blood as Violet.
At the end of the episode, you can see 221 Baker Street, Apartment B, which refers to Sherlock Holmes.