During his late adolescence Schiele's emotions were directed into an intense relationship with his younger sister, Gerti, which was not without its incestuous implications.
"In 1909 he left the Academy, after completing his third year. He found a flat and a studio and set up on his own. At this time he showed a strong interest in pubescent children, especially young girls, who were often the subjects of his drawings.
Already a superb draughtsman, Schiele made many drawings from these willing models, some of which were extremely erotic. He seems to have made part of his income by supplying collectors of pornography, who abounded in Vienna at that time.
In 1911 Schiele met the seventeen-year-old Wally Neuzil, who was to live with him for a while and serve as the model for some of his best paintings. Little is known of her, save that she had previously modelled for Klimt, and had perhaps been one of the older painter's mistresses.
They then moved to the equally small town of Neulengbach, half an hour from Vienna by train. just as it had been in Vienna, Schiele's studio became a gathering place for all the delinquent children of the neighbourhood. His way of life inevitably aroused animosity, and in April 1912 he was arrested.
"Schiele's narcissism, exhibitionism and persecution-mania can all be found united in the poster he produced for his first one-man exhibition in Vienna, held at the Galerie Arnot at the very beginning Of 1915, in which he portrayed himself as St Sebastian.
From Edward Lucie-Smith, "Lives of the Great 20th-Century Artists"
http://www.artchive.com/artchive/S/schiele.html