" CASE 146. Once summer's evening, at twilight, X.Y., a doctor of medicine in a North German city, was trodden on by a watchman as he (the doctor) was committing an immoral act with a tramp on a path in a field. He was practicing masturbation on him and thereupon putting the tramp's penis into his mouth. "

― Richard von Krafft-Ebing , Psychopathia Sexualis: A Medico-Legal Study