This is true! Actually, they sing about getting laid a lot, which is something I did not realize when I saw the movie for the first time in tenth grade. It makes me love it so much more!

My library has it! Once I've worked my way through the Diana Wynne Jones oeuvre (thanks for your GIANT LIST, by the way. There are a few I hadn't read because they were out of print when I was a kid and my library didn't have them).