In 1907, Demorest decided to pursue a career in art. He studied drawing for several months, in South America.  After returning to America, Demorest spent six months studying at the School of the Museum of Fine Arts in Boston and illustrated The Bishop's Men, published by Herbert L. Turner.  Demorest then went to New York to study at th e Art Students League where he worked under Frank Vincent Du Mond.  While in New York
Demorest illustrated a book published by D. Appleton and Company.

Having heard Howard Pyle Lecture at the Art Students League, Demorest came to Wilmington in the spring of 1908. For a while Demorest had a studio at 804 Orange Street. Then he used the top floor of his parents home on South Clayton Street for a studio, which he shared for a short time with W.H.D. Koerner, another Pyle pupil he had known at the Art Students League. While in Wilmington, Demorest worked for various children's magazines in Philadelphia and also illustrated several books For the Reed Publishing Company of Boston. In addition to drawing several covers, for the Christian Herald Magazine he also worked for Gunthers, Smith's, and Boy's Magazine.

Demorest exhibited in the Wilmmgmn Society of the Fine Arts'  annual exhibit while serving as Vice Counsel of Paraguay at Wilmington from 1913 to 1018. At the time of his induction into the army in July 1918, Demorest listed his occupation as author and illustrator, and he is known to have written same short stories. As a first lieutenant during World War 1, Demorest served on the General Staff on the Military Intelligence Division as a military attache at the embassy in Brazil. In 1921 he became U.S. Vice Consul to Trinaidad and later served also as Consul to British, French, and Dutch Guiana and Grenada. In January 1934, he received the Scroll of Merit from the Chinese government. Demorest died suddenly at his home in Trinidad on November 16, 1934.

Pyle Students