She: (Pissed off, in french) "va te faire enculer espece de gros tas de merde, j'en ai ras-le cul de vos conneries, merde!!! je rentre!!!" (not meaning you should follow her to her place)
The phrase "Voulez-vous coucher avec moi?" actually appeared before the song, in the play "A Streetcar Named Desire" by Tennessee Williams, and a poem by E.E. Cummings. The phrase is puzzling as it uses formal language ("vous" is the formal way to say "you") while describing an intimate act (the phrase literally means "Do you want to come to bed with me?"). This leads many to believe that the phrase is tied with prostitution.
"Voulez-vous coucher avec moi ce soir?" is the formal way of saying "Would you like to come to bed with me this evening", as opposed to the informal "Veux-tu coucher avex moi".
Actually, "Lady Marmalade" was not by Patti Labelle, but by the group Labelle, a band she fronted. Nona Hendryx and Sarah Dash rounded out the trio. "Lady Marmalade" was written by Bob Crewe and Kenny Nolan and was featured on Labelle's 1974 album Nightbirds.