The book about the sneezing panda is a reference to the Chu books by Neil Gaiman, who introduced the character Lucifer in the comic book series The Sandman.
The song playing in LUX at the start of the episode is "Rebel Rebel" by David Bowie. In the graphic novels the show is based on, Lucifer is depicted as looking like David Bowie.
Lucifer noticeably wears red soled shoes on his way to the first crime scene, reminiscent of luxury shoe brand Louboutin (which does have a men's line).
The title is a play on a Latin line in the William Shakespeare play Julius Caesar, Act 3, Scene 1: "Et tu, Brute," meaning "and you, Brutus." When Caesar is betrayed and ultimately assassinated, he says so to his friend Marcus Junius Brutus.
The title is said by Lucifer.