The Little Sister

The Little Sister is a 1949 novel by Raymond Chandler, the fifth in his popular Philip Marlowe series.
The story opens when mousy Orfamay Quest first phones and then visits Philip Marlowe's office in search of a detective. Orfamay is a "small, neat, rather prissy-looking girl with primly smooth brown hair and rimless glasses" from Manhattan, Kansas who has come to Los Angeles to search for her older brother Orrin.