From the song, "Shapoopie," as seen in "The Music Man," a play about a man from Gary, Indiana who makes a boys band in Iowa and falls in love with a librarian.
Shapoopie, shapoopie, the girlthat's hard to get.
Shapoopie, shapoopie, but you can win her yet.
The girl who is hard to get. As seen in the long-standing well received musical "The Music Man". Contrary to popular belief this term was not coined or conceived of by Seth Macfarlane.