The Pussycat Dolls is a much more complex organization than many people realize.
The Lounge incorporates music by the Pussycat Dolls (shown below in both real-life and Music Lounge form), hence the PCD in the name.
Pussycat Dolls lyrics are on the lips of fans of the girl group all over the world.
Part of the fun of a Pussycat Dolls show is singing along with the group, so if you're scratching your head as to what they're saying, there are tons of websites out there that help you can get it all down.
Other members of the group include the large number of girls that perform in the Pussycat Dolls Lounge - the group's famous Las Vegas show.