Miley Cyrus celebrated her 17th birthday with an '80's themed party on Wednesday night, and always the example of good taste and appropriateness, Miley dressed as Julia Roberts "hooker" character from "Pretty Woman."

The teen star -- recently criticized for pole dancing at the Teen Choice Awards -- donned the sexy outfit and danced the night away at the Canal Room on West Broadway, where Constantine Maroulis and the cast of the Broadway hit "Rock of Ages" surprised Miley with a performance.

Sources told Page Six: "Miley had seen the show two weeks ago and loved it, so her mom Tish brought the cast in to surprise her. But I'm not sure who was more into Constantine -- Miley or her mother." Between songs from the musical, Miley grabbed Constantine and danced with him at the front of the stage and then Tish joined in. (Source)

Jesus, poor Constantine. I don't know what sounds more terrifying; an underage girl dressed like a prostitute grinding up against him, her 40-something mother or both of them at the same time. I guess one could argue that's how pornos start, but same goes for probation stints and lifetimes of therapy.

Miley and "Tish" skanking it up together at the Teen Choice awards in August: